Question

Complete the second sentence so that it means the same as the first1) I’ m almost sure you left your phone in the restaurant. You ____ ____ left your phone in the restaurant. 2) Why didn’t you tell me it was your birthday?You ____ ____ _____ me it was your birhday!

Answer 1

1) You must have left your phone in the restaurant.

In this sentence, it is appropriate to use the modal verb must with a past reference to imply a degree of certainty, like the phrase in the original sentence almost sure. In this respect, the modal verb is used to express a high level of possibility.  

2) You should have told me it was your birthday.

In this case, the modal verb should along with have told expresses an advice with a past reference. The modal verb should is always related to the function of giving advice.  

Answer 2

1.Almost had
2. You forgot to tell