I don’t know with this problem.It’s too hard.
Lucy knew nothing about it ___________ her sister told her.
He can play tennis better than ___________ in the class.
The old man lives ___________ , but he never feels ___________ .
—Do you know mother giant pandas have only one or two babies ___________?— Sorry, I don’t know.
— Is this maths problem ___________?— Yes, I can work it out ___________ .