Isimply couldn’t understand how it _______ that you did so much work in such a short time.
A lot of children never fully ______ their mothers until it is too late.
______ I admit that there are problems, I don't agree that they cannot be solved.
Small _____ it is, the pen is a most useful tool.
______ it is getting dark.,we’d better hurry
_____ she was very tired, she went on working.