He____know the answer, but I’m not sure.A. maybe B. may be C:may D. must
---Mr. Black, I find ______ difficult to play the piano well. ---Oh, I think you just need to practice more
The old woman has no children. She lives by________.
_______ has donated much money to the charity .
Some of the CDs belong to her, while the rest are ________.
I like junk food very much, but I eat ______ only once a month.