This grammar exercise tests your understanding of modal auxiliary verbs. Fill in the blanks.
1She ............... busy at that time.
Select 2 answers.
Wrong!
Use "might have been" or "may have been" to talk about a possible situation in the past.
2It ............... there. I clearly remember putting it there.
Wrong!
Use "must be" when you are sure about a present fact.
3You ............... mistaken.
Wrong!
Use "must be" before an adjective when you are sure about a present situation.
4He ............... by now.
Wrong!
Use "should have arrived" to say an expected arrival is probably complete by now.
5It ............... an accident.
Wrong!
Use "might have been" to talk about a possible explanation for a past event.
6He ............... ill yesterday.
Wrong!
Use "might have been" with a past time expression such as yesterday.
7Nobody is answering the doorbell. They ............... out.
Wrong!
Use "must have gone" when present evidence makes you sure someone left earlier.
8Where is Dad? He ............... in his room.
Select 2 answers.
Wrong!
Use "must be" or "may be" to talk about where someone probably or possibly is now.
9He is not in his chair. He ............... to the cafe.
Wrong!
Use "might have gone" to suggest a possible completed movement before now.
10We ............... waited for him.
Wrong!
Use "needn't have" before a past participle for an unnecessary action that happened.
11You ............... for me. You can leave when you are ready.
Wrong!
Use "needn't wait" to say there is no present or future obligation to wait.
12She left work at 6. She ............... here soon.
Wrong!
Use "should be" to say something is expected to happen soon.
Done.
Score: 0/12
Answers
- She might have been / may have been busy at that time.
- It must be there. I clearly remember putting it there.
- You must be mistaken.
- He should have arrived by now.
- It might have been an accident.
- He might have been ill yesterday.
- Nobody is answering the doorbell. They must have gone out.
- Where is Dad? He must be / may be in his room.
- He is not in his chair. He might have gone to the cafe.
- We needn’t have waited for him.
- You needn’t wait for me. You can leave when you are ready.
- She left work at 6. She should be here soon.

