She looks very sad. I want to help her, but I just don’t know ____ to do it.

—Is this         new book, Shirley?—No, it isn’t. Maybe it’s           .

 It’s my mother’s birthday tomorrow. I will buy _____ a CD as a present.

 My school bag is larger than _________.            

I find        difficult for Tom to reach that picture.He is a little short.