Answer Key

Exercise

Complete the following sentences with the correct form of the verb in brackets...
  1. I really haven't  [been able to] (BE ABLE) study lately because of my terrible headaches. 
  2. I don't know why she isn't here yet – she  [might have left] (MIGHT LEAVE) work late. 
  3. You called twice! I didn't hear the phone – I  [must have been] (MUST / BE) asleep! 
  4. You  [mustn't, must not] (MUST) get there - that area is restricted! 
  5. You  [can't have seen, cannot have seen, could not have seen, couldn't have seen](CAN / SEE) her downtown last night. She's been out of the country since Tuesday. 
  6. I'm so sorry I  [couldn't, could not] (CAN) come, but my cat was in a tree and I had to help her get down. 
  7.  [were] you  [allowed to] (BE ALLOWED) change anything in the document? 
  8. Don't be so hard on yourself - there was nothing you  [could have done] (CAN / DO) for him anyway - it was too late to save him. 
  9. Anne  [didn't have to, did not have to] (HAVE TO) prepare anything for the meeting last Monday; everything had been prepared by her assistant. 
  10.  [shouldn't have had, should not have had] (SHOULD / HAVE) those last three beers - now I can't take the car home.