It’s hard to say what kind of person he is. Sometimes he is very nice; at other times he _______ be very cold.

I really don’t know how to thank you , but for your help, I ______ my lost necklace．

-- Do you still remember when we went to Nanjing?--- I can’t remember now but _________ sometime last summer?

We were all surprised when he made it clear that he ___ office soon.

The doctor suggested he ______.