高中英语现在进行时专项复习及答案

这是一份高中英语现在进行时专项复习及答案，共19页。
高中英语专项复习：一般现在时
第一部分:1-50 专项练习 第二部分:51-100全面解析

1．At present, many new workers ________ and in six months they will be sent to build a new railway.
A．are being trained B．are training
C．will train D．will be trained
2．—Where is Mother?
—She is in the kitchen. She ______ the housework all morning.
A．is doing B．was doing C．has done D．has been doing
3．While China an anti-terrorist security network, the nation still needs to prepare its people the war on terror, therefore its powerful weapon.
A．knits, to fight, to gather B．is knitting, fighting, gathering
C．is knitting, to fight, gathering D．has knitted, to fight, gathering
4．Hurry! The plane ________. You know, it ________ at 3:15.
A．takes off, takes off B．is taking off, takes off
C．takes off, is taking off D．is taking off, is taking off
5．It is reported that more than one new house________ at present in the disaster area.
A．has been built B．have been built
C．is being built D．are being built
6．Selecting a mobile phone is no easy task because technology_______ so rapidly.
A．has changed B．is changing
C．will have changed D．will changed
7．With the development of science, more new technology ______ to the fields of IT.
A．has introduced B．is being introduced
C．is introduced D．was introduced
8．—Hi, let's go skating.
—Sorry, I'm busy right now. I in an application form for a new job.
A．fill B．have filled C．will fill D．am filling
9．What a helpful girl she is! ___________. Which sentence can Not be best used to praise the girl highly?
A．She always helps others. B．She is continually helping others.
C．She is constantly helping others. D．She is always helping others.
10．—Are we about to having dinner?
—Yes, it ________ in the dining room.
A．serve B．is serving
C．is being served D．has been serving
11．John as well as the other children who no parents down on in the school.
A．has; is looking B．have; are looking
C．have; is being looked D．have; are being looked .
12．Now the world's attention ________ the stocking markets, as they have great influence on the world's economy.
A．is fixing on B．is being fixed on
C．has fixed on D．had been fixed on
13．My watch is broken. It _____.
A．is repairing B．is being repaired
C．has been repaired D．has repaired
14．A new cinema _____ here. They hope to finish it next month.
A．will be built B．is being built C．has been built D．is built
15．Would you please keep silent? The weather report ________ and I want to listen.
A．is broadcasted B．is being broadcasted
C．has been broadcasted D．had been broadcast
16．Professor Johnson, along with his students, ________ on the program day and night to meet the deadline nowadays.
A．were working B．are working C．was working D．is working
17．Local governments to strengthen water transport safety management recent fatal accidents.
A．are urging, followed B．are being urged, following
C．are urged, to follow D．urge, being followed
18．—Hi，Tony，can I use your computer for a while this afternoon?
—Sorry.________.
A．It's repaired B．It has been repaired
C．It's being repaired D．It had been repaired
19．Kimberly ______ an article, so don't disturb her.
A．would write B．writes C．wrote D．is writing
20．With rural ecosystem improving, the number of tourists to villages ________ year by year.
A．have increased B．increases C．is increasing D．are increasing
21．—Have you moved into the new house?
—Not yet. It .
A．has been built B．was built C．is being built D．had been built
22．—Have the parts we need for the copying machine arrived yet?
—I ordered them last week, but something ________ them up.
A．holds B．is going to hold
C．will hold D．is holding
23．A large park ________here now.They hope to finish it in three months.
A．is built B．will be built C．has been built D．is being built
24．—Mum, is the pair of gloves ________ mine?
—Yes. You have to wear another pair.
A．washing B．have washed C．being washed D．having washed
25．He is _____ his lesson _____ the final exam.
A．preparing; to B．preparing; for C．ready; to D．ready; for
26．Large quantities of meat _______ sold in that store at the present time.
A．are being B．is being C．will be D．is
27．Would you please keep silent? The weather report__________, and I want to listen.
A．is broadcast B．is being broadcast
C．has been broadcast D．had been broadcast
28．John as well as the other children who ______ no parents ______ good care of in the center.
A．have; is being taken B．have; has taken
C．has; is taken D．has; have been taken
29．—I have just got Michelle Obamas's memoir "Becoming" from an American friend.
—Really? The book _______ into Chinese and is expected to be released next year.
A．translates B．will translate
C．has been translated D．is being translated
30．— Can we play basketball in the school gym?
— No, it ______ during the summer holidays.
A．is repaired B．is being repaired
C．was repaired D．has been repaired
31．— You know, a new park _______ near the river now.
— Wow, we'll have a good place to relax in the future.
A．building B．will build C．to be built D．is being built
32．We must hurry up. The last train ___________ in 10 minutes.
A．is leaving B．leaves
C．is about to leave D．left
33．Chinese people's spending on overseas trips ______ year by year.
A．had risen B．Rise C．is rising D．rose
34．My brother wants to work in the factory which ____
A．is building B．has been built
C．is being built D．is to be built
35．My smart watch battery slow. It needs charging.
A．runs B．is run C．ran D．is running
36．—What is that noise?
— Oh, I forgot to tell you. The new machine ______.
A．is being tested B．was tested
C．will be tested D．has been tested
37．I ________ Beijing in a few days. Do you know when the earliest plane ________?
A．am leaving for; takes off B．leaves for; takes off
C．am leaving for; is taking off D．leave for; is taking off
38．— When can we move to the new apartment?
— Well, it ______, and hopefully, the job will be done in a couple of weeks.
A．is being decorated B．is decorated
C．was decorated D．had decorated
39．—Shall we ask Bob to help us do the work?
—Sure. Time _____and we have a lot to do tonight.
A．is run out B．is running out
C．has been run out D．was run out
40．Right now the new product ________ in the laboratory.
A．is developing B．develops
C．is being developed D．developed
41．—How did you get on in your final exam?
—I have no idea. The papers .
A．are being marked B．would be marked
C．have been marked D．had been marked
42．Look! They ______ a good time, ______ they?
A．have; do B．have; don't
C．are having; are D．are having; aren't
43．—Do you live in the neighborhood near Nanjing Road?
—No. I _______ there these days to visit my uncle.
A．have stayed B．would stay C．had stayed D．am staying
44．My washing machine ________ this week, so I have to wash my clothes by hand.
A．was repaired B．is repaired
C．is being repaired D．has been repaired
45．My new apartment painted now, so I have to wait another month to move in.
A．is being B．has been C．is D．will be
46．—Monitor?
— I'm not monitor of our class. I __ with the teacher until the monitor is elected.
A．will just help B．am just to help
C．am just helping D．have just helped
47．Nowadays with the development of science, more and more new technology____ to the fields of IT.
A．has introduced B．was introduced
C．will introduce D．is being introduced
48．— Have you seen Steven this morning?
—Yes! Steven, together with his wife, ________ the guests of the party now.
A．greets B．greet C．is greeting D．are greeting
49．Lots of roads ______ these days. We'd better set out earlier.
A．are repaired B．have been repaired
C．are being repaired D．are repairing
50．In the rainforest of the Amazon, 50 to 150 plant species ______ every day.
A．are being destroyed B．are destroying
C．have been destroyed D．Destroyed




答案解析部分
1．A
2．D
3．C
4．B
5．C
6．B
7．B
8．D
9．A
10．C
11．C
12．B
13．B
14．B
15．B
16．D
17．B
18．C
19．D
20．C
21．C
22．D
23．D
24．C
25．B
26．A
27．B
28．A
29．D
30．B
31．D
32．A
33．C
34．C
35．D
36．A
37．A
38．A
39．B
40．C
41．A
42．D
43．D
44．C
45．A
46．C
47．D
48．C
49．C
50．A


高中英语专项复习：一般现在时
第一部分:1-50 专项练习 第二部分:51-100全面解析
1．At present, many new workers ________ and in six months they will be sent to build a new railway.
A．are being trained B．are training
C．will train D．will be trained

全面分析：考查现在进行时态的被动语态。句意：目前， 许多工人正在接受训练，在六个月后他们将会被送去建造一条新的铁路。表示正在接受训练，所以是A。

2．—Where is Mother?
—She is in the kitchen. She ______ the housework all morning.
A．is doing B．was doing C．has done D．has been doing

全面分析：考查动词时态。句意：——母亲在哪里？——她在厨房里。一上午她都在做家务。现在仍在厨房做，故应用现在完成进行时，表示从过去至今一直在持续的动作。关键词是：all morning。故选D。

3．While China an anti-terrorist security network, the nation still needs to prepare its people the war on terror, therefore its powerful weapon.
A．knits, to fight, to gather B．is knitting, fighting, gathering
C．is knitting, to fight, gathering D．has knitted, to fight, gathering

全面分析：考查动词时态和非谓语动词。句意：当中国正在联合反恐怖安全网络的时候，这个国家还需要使人民准备好反恐战争，因此要集聚它的强大武器。题干讲到的是现在正在从事的事情要用现在进行时。第二个空考查prepare somebody to do“使某人准备做某事”。第三个空格作状语，主语“国家”和动词“聚集”是主谓关系，用现在分词。故选C。

4．Hurry! The plane ________. You know, it ________ at 3:15.
A．takes off, takes off B．is taking off, takes off
C．takes off, is taking off D．is taking off, is taking off

全面分析：快点！飞机就要起飞了。你知道，飞机是3：15起飞。某些表示位置转移的词可以用现在进行时表示最近或较近的将来。从语境可知飞机马上就要起飞了，所以用is taking off；而按照时刻表规定的要发生的事情要用一般现在时表示将来，所以第二个空用takes off，故答案为B。

5．It is reported that more than one new house________ at present in the disaster area.
A．has been built B．have been built
C．is being built D．are being built

全面分析：据报道，目前灾区正在建造不止一幢新房子。根据at present可知，此处应用现在进行时。动词build意为“建造”，和主语house构成被动关系。“more than one+可数名词单数”做主语，谓语动词用单数。故选C。

6．Selecting a mobile phone is no easy task because technology_______ so rapidly.
A．has changed B．is changing
C．will have changed D．will changed

全面分析：挑选手机不是容易的活，因为技术正如此之快地变化着。现在进行时态在此表示了一种“持续变化”的状态，体现了“变化、趋势、发展和进展”，故选B。
7．With the development of science, more new technology ______ to the fields of IT.
A．has introduced B．is being introduced
C．is introduced D．was introduced

全面分析：句意，随着科技的发展，更多新的技术被引进到IT领域。表示现阶段正在进行的动作，用现在进行时。且主语new technology与动作introduce之间是被动关系，用现在分词的被动语态，故选B。

8．—Hi, let's go skating.
—Sorry, I'm busy right now. I in an application form for a new job.
A．fill B．have filled C．will fill D．am filling

全面分析：考查时态。句意：——嗨，咱们去滑冰吧。——对不起，我现在忙着呢。我正在填一张新工作申请表。根据题干中的I'm busy right now可推知fill in这一动作正在进行，故用现在进行时。答案为D。

9．What a helpful girl she is! ___________. Which sentence can Not be best used to praise the girl highly?
A．She always helps others. B．She is continually helping others.
C．She is constantly helping others. D．She is always helping others.

全面分析：考查动词的时态。句意：她是多么助人为乐的女孩啊！她总是帮助别人。频度副词always，continually，constantly用于进行时态表示感情的喜恶，即对某件事情的喜欢或者抱怨。故只有A项不符合语境。故选A。

10．—Are we about to having dinner?
—Yes, it ________ in the dining room.
A．serve B．is serving
C．is being served D．has been serving

全面分析：—我们准备去吃饭吗？—是的，饭菜正在餐厅被供应。it是指饭菜，和动作serve之间是被动关系，且动作正在进行，四个选项中只有C项是现在进行时的被动语态，故选C。

11．John as well as the other children who no parents down on in the school.
A．has; is looking B．have; are looking
C．have; is being looked D．have; are being looked .

全面分析：考查主谓一致。句意：约翰和其他没有孩子的父母在村子里被照顾的很好。who引导的是定语从句，根据句意，应该做children的定语，所以定语从句的谓语动词用复数have. 第二个横线处要填的是主句的谓语动词。主句的主语是John as well as the other children,谓语和John一致，是单数，所以谓语动用单数。这里要用被动语态。所以选C。

12．Now the world's attention ________ the stocking markets, as they have great influence on the world's economy.
A．is fixing on B．is being fixed on
C．has fixed on D．had been fixed on

全面分析：现在世界关注的焦点都在股票市场上，因为它们对世界经济已经产生了很大的影响。 attention与focus之间为被动关系，Now提示用现在进行时。故选B。

13．My watch is broken. It _____.
A．is repairing B．is being repaired
C．has been repaired D．has repaired

全面分析：我的表坏了，正在修理。根据My watch is broken可知表正在被修理，故选B项。

14．A new cinema _____ here. They hope to finish it next month.
A．will be built B．is being built C．has been built D．is built

全面分析：这儿有个新的电影院在建。预期下个月完工。根据情景可知是正在发生的事，所以应用现在进行时的被动语态，故选B。
15．Would you please keep silent? The weather report ________ and I want to listen.
A．is broadcasted B．is being broadcasted
C．has been broadcasted D．had been broadcast

全面分析：考查动词时态和语态。根据语境，天气预报应该是正在播报，故应用现在进行时。the weather report 和broadcast应是被动关系，故应用被动语态。综上所述，此题应选B。
16．Professor Johnson, along with his students, ________ on the program day and night to meet the deadline nowadays.
A．were working B．are working C．was working D．is working

全面分析：约翰逊教授和他的学生们为了在最后期限前完成这个项目，现在正夜以继日地工作。根据时间状语nowadays可知表示现阶段正在进行的动作，应用现在进行时。故选D。

17．Local governments to strengthen water transport safety management recent fatal accidents.
A．are urging, followed B．are being urged, following
C．are urged, to follow D．urge, being followed

全面分析：最近接连发生的致命事故敦促地方政府加强水路运输安全管理。urge sb. to do sth.，固定搭配， “敦促某人做某事”。分析句意可知是事故促使政府加强管理。因此政府与敦促是被动关系，故A与D是错误的。事件已发生了故不能用to follow作定语， following，“后面的，其次的，下列的”。因此要用B。

18．—Hi，Tony，can I use your computer for a while this afternoon?
—Sorry.________.
A．It's repaired B．It has been repaired
C．It's being repaired D．It had been repaired

全面分析：—Torry,我今天下午能用一会你的电脑吗？—对不起，它正在被修理。根据句意Torry的电脑在说话的时候正在被修，所以用现在进行时的被动，所以选C。
19．Kimberly ______ an article, so don't disturb her.
A．would write B．writes C．wrote D．is writing

全面分析：本题考查时态，根据句意，选用现在进行时，表示说话时刻正在进行的动作。A would write 过去将来时，必须和一般过去时结合使用，表示过去的将来；B writes 一般现在时，表示经常、习惯的动作；客观真理；现在的事实或状态；代替一般将来时；C wrote 一般过去时，表示过去的动作，与现在无关。
20．With rural ecosystem improving, the number of tourists to villages ________ year by year.
A．have increased B．increases C．is increasing D．are increasing

全面分析：随着乡村生态系统的改善，到乡村旅游的人数正在逐年增加。此处强调动作正在进行，应用现在进行时，且the number of表示“……的数目”，中心词是number，所以是单数，作主语时，谓语动词用单数。故选C。

21．—Have you moved into the new house?
—Not yet. It .
A．has been built B．was built C．is being built D．had been built

全面分析：—你搬进新家了吗？—仍旧没有，它仍旧正在建设。根据语境可知，It指代上文提到的the new house，是第三人称单数，与built是被动关系，用被动语态，结合句意，built这一动作表示正在进行的动作。故选C。

22．—Have the parts we need for the copying machine arrived yet?
—I ordered them last week, but something ________ them up.
A．holds B．is going to hold
C．will hold D．is holding

全面分析：考查时态。句意：—我们需要的复印机零部件送来了吗?—我上周就已定货，但不知什么事阻碍了。根据上一句的提问可知，上周定的货还没有到，说明有事情正在阻止这些货物的到来，故要用现在进行时态，故选D。

23．A large park ________here now.They hope to finish it in three months.
A．is built B．will be built C．has been built D．is being built

全面分析：考查被动语态。句意：一个大公园现在正在被修建，根据句意可知用现在进行时的被动语态。故选D。

24．—Mum, is the pair of gloves ________ mine?
—Yes. You have to wear another pair.
A．washing B．have washed C．being washed D．having washed

全面分析：——妈妈，这双正洗的手套是我的吗？——是的。你不得不带另一双了。根据下文可知，手套是正在被洗，用现在进行时的被动，故选C。

25．He is _____ his lesson _____ the final exam.
A．preparing; to B．preparing; for C．ready; to D．ready; for

全面分析：考查固定搭配。 prepare —for 为—做准备；be ready for为—做准备。 根据题意 表示正在进行的动作 所以选B。

26．Large quantities of meat _______ sold in that store at the present time.
A．are being B．is being C．will be D．is

全面分析：现在那家商店正在出售大量的猪肉。large quantities of固定短语，“大量的”，做主语后面的谓语动词要和quantities保持一致，主语是复数形式，故为A。

27．Would you please keep silent? The weather report__________, and I want to listen.
A．is broadcast B．is being broadcast
C．has been broadcast D．had been broadcast

全面分析：根据句意：能请您保持安静吗？天气预报正在播放，我想听呢。所以此处是现在进行时。天气预报是被播报的，所以用被动。
28．John as well as the other children who ______ no parents ______ good care of in the center.
A．have; is being taken B．have; has taken
C．has; is taken D．has; have been taken

全面分析：考查定语从句与语态，句意：John和其他没有父母的孩子在这个中心得以很好的照顾。分析句子结构，who引导的定语从句修饰先行词children, children是复数，所以定语从句的谓语动词也要用复数，故排除C和D; 且根据句意，强调孩子们应该是“目前正被照顾”，应用被动语态，故选A.
29．—I have just got Michelle Obamas's memoir "Becoming" from an American friend.
—Really? The book _______ into Chinese and is expected to be released next year.
A．translates B．will translate
C．has been translated D．is being translated

全面分析：“我刚从美国朋友那里搞到一本米歇尔•奥巴马的回忆录《成为》。” “真的呀？此书正在翻译中，预计明年发行。”此刻正在翻译成中文，故使用现在进行时，而且与主语是被动关系。故选D。

30．— Can we play basketball in the school gym?
— No, it ______ during the summer holidays.
A．is repaired B．is being repaired
C．was repaired D．has been repaired

全面分析：--我们可以在学校操场上打篮球吗？--不行，暑假期间操场正在被修葺。根据句意可知，这里是表示正在进行，所以要用现在进行时。主语it和动词之间是被动关系，所以要用被动语态。故选B。

31．— You know, a new park _______ near the river now.
— Wow, we'll have a good place to relax in the future.
A．building B．will build C．to be built D．is being built

全面分析：——你知道，一个新的公园正在河边修建。——哇，将来我们就有一个放松的好地方了。A、C项是非谓语动词形式，不能在句中作谓语，故排除；主语park和动词build之间是被动关系，应用被动语态，排除B项；根据“Wow, we’ll have a good place to relax in the future.”可知，此处表示公园正在建设中，应用现在进行时的被动语态。故选D。

32．We must hurry up. The last train ___________ in 10 minutes.
A．is leaving B．leaves
C．is about to leave D．left

全面分析：我们必须快点。最后一班火车10分钟后就要开了。此处应表将来含义，如arrive，come，get (to)，leave，return，start，travel，take，take off，fly，see off表示位置转移的动词(短语)，用现在进行时（am/is are doing）表将来的含义，主要用于按计划或安排将要发生的动作或事件。故选A。

33．Chinese people's spending on overseas trips ______ year by year.
A．had risen B．Rise C．is rising D．rose

全面分析：中国人出国旅游的花费在逐年增加。本句的主语是“Chinese people's spending on overseas trips”中国人花在出国旅游上的费用，这是一个表示金钱的名词，作主语时谓语动词用单数，且本句表示的是最近这阶段一直以来的情况，所以使用现在进行时。故选C。

34．My brother wants to work in the factory which ____
A．is building B．has been built
C．is being built D．is to be built

全面分析：我哥哥想去那个正在被建的工厂工作。the factory和build是被动关系，用现在进行时的被动，选C。


35．My smart watch battery slow. It needs charging.
A．runs B．is run C．ran D．is running

全面分析：我的智能手表快没电了，需要给它充电。本句为现在进行时表示将来。故选D。

36．—What is that noise?
— Oh, I forgot to tell you. The new machine ______.
A．is being tested B．was tested
C．will be tested D．has been tested

全面分析：——那是什么声音？——哦，我忘了告诉你了。新机器正在测试中。此处表示正在进行的动作，使用现在进行时，主语The new machine和test为被动关系，现在进行时被动语态的基本构成形式是：am/is/are being done。故选A。

37．I ________ Beijing in a few days. Do you know when the earliest plane ________?
A．am leaving for; takes off B．leaves for; takes off
C．am leaving for; is taking off D．leave for; is taking off

全面分析：考查动词时态。in the few days表示将来时，应该用be going to 或 will do的形式填空，但leave/come/go/fly可用进行时态表示将来；而Do you know when是插入语，when引导的宾语从句应该用一般现在时，因为飞机起飞的时间是固定的。故选A。
38．— When can we move to the new apartment?
— Well, it ______, and hopefully, the job will be done in a couple of weeks.
A．is being decorated B．is decorated
C．was decorated D．had decorated

全面分析：—我们什么时候才能搬到新公寓里去啊？—额，这个新公寓正在装修呀，有希望可以在几周内装修好，那时我们就能搬过去了。公寓正在被装修，现在进行时，被动，选A。

39．—Shall we ask Bob to help us do the work?
—Sure. Time _____and we have a lot to do tonight.
A．is run out B．is running out
C．has been run out D．was run out

全面分析：——我们要不要请鲍勃帮我们做这项工作？——当然。 时间不多了，今晚我们有很多事情要做。根据句意可知指“快没有时间了”，应用现在进行时，故选B。

40．Right now the new product ________ in the laboratory.
A．is developing B．develops
C．is being developed D．developed

全面分析：现在这个新产品正在实验室里开发。此处是谓语动词，develop与主语 the new product 之间是被动关系，应用被动语态，结合时间状语 right now ，可知应用现在进行时，故选C。

41．—How did you get on in your final exam?
—I have no idea. The papers .
A．are being marked B．would be marked
C．have been marked D．had been marked

全面分析：—期末考试你考得怎么样？—我不知道,试卷正在批改。A. are being marked “正在被批改”； B. would be marked“（过去）将要被批改”；C. have been marked“已被批改”；D. had been marked“（在过去某个时间点前）已批改”。根据上一句“期末考试你考得怎么样？”“—我不知道”可判断出试卷“正在被批改”，所以才不知道。因此C与D是错误的。B的时间不一致，故不能选。试卷the papers与动词mark二者是被动关系，所以要用现在进行的被动语态，故选A。

42．Look! They ______ a good time, ______ they?
A．have; do B．have; don't
C．are having; are D．are having; aren't

全面分析：看!他们玩得很开心，不是吗?根据look 可知，用现在进行时。反意疑问句后面要和前面的时态相同，前面是肯定形式，反意疑问句用否定形式。故填D。

43．—Do you live in the neighborhood near Nanjing Road?
—No. I _______ there these days to visit my uncle.
A．have stayed B．would stay C．had stayed D．am staying

全面分析：——你住在南京路附近住吗？——不。这些天我来看望我的叔叔就一直住在那里。表示现在进行的动作用现在进行时，故选D。

44．My washing machine ________ this week, so I have to wash my clothes by hand.
A．was repaired B．is repaired
C．is being repaired D．has been repaired

全面分析：这周我的洗衣机正在修，所以我不得不手洗衣服。根据后句so I have to wash my clothes by hand. 可知，洗衣机正在修，故用现在进行时态的被动语态。故选C。

45．My new apartment painted now, so I have to wait another month to move in.
A．is being B．has been C．is D．will be

全面分析：我的新公寓正在粉刷,所以我得再等一个月才能搬进来。根据时间状语now，可知房子现在还在装修中，即刷漆应该是正在进行，所以用现在进行时，又因为my new apartment与paint之间为逻辑上的动宾关系，所以用被动结构，因此谓语动词用现在进行时的被动语态，选A。

46．—Monitor?
— I'm not monitor of our class. I __ with the teacher until the monitor is elected.
A．will just help B．am just to help
C．am just helping D．have just helped

全面分析：—班长？—我不是班长，我只是帮老师忙直到班长选出来。说明帮忙是暂时的，现在进行时可以表示现阶段暂时的动作，选C。

47．Nowadays with the development of science, more and more new technology____ to the fields of IT.
A．has introduced B．was introduced
C．will introduce D．is being introduced

全面分析：现在，随着科技的发展，越来越多的新科技正在被引入IT行业。根据时间状语nowadays可知，此句要用现在进行时，主语technology与谓语introduce之间是被动关系，因此要用现在进行时的被动语态be being done，故选D。

48．— Have you seen Steven this morning?
—Yes! Steven, together with his wife, ________ the guests of the party now.
A．greets B．greet C．is greeting D．are greeting

全面分析：——你今天早上见到史蒂文了吗？——是的！现在Steven和他的妻子正在一起欢迎宴会上的客人。together with连接两个主语时，谓语动词与前面的主语保持一致，所以空处谓语应与主语Steven保持一致；句中时间状语“now(现在)”和句意可知，句子时态为现在进行时，需使用be doing的形式，主语为单数。故选C。

49．Lots of roads ______ these days. We'd better set out earlier.
A．are repaired B．have been repaired
C．are being repaired D．are repairing

全面分析：这些天很多路正在修理。我们最好早点出发。根据these days和set out earlier可知，动作目前正在进行，再根据句子主语roads是复数形式，和谓语动词repair之间是被动关系，所以此处用现在进行时态的被动语态。故选C。

50．In the rainforest of the Amazon, 50 to 150 plant species ______ every day.
A．are being destroyed B．are destroying
C．have been destroyed D．destroyed

全面分析：在亚马孙雨林中有50-150种植物物种每天正在被破坏。因为是现阶段正在发生的事情，所以用现在进行时，而且50 to 150 plant species和destroy之间是被动关系，所以选A。