I wonder _________ Mary has kept her figure after all these years.—By working out every day.

Why do you look so upset —I broke up with my girlfriend.If only I _______ more about her.

I think the book is as interesting as it is instructive．—— It could never be____．It is well worth reading．

ents, without ______ help I wouldn’t have becomewho I am, have taught me the true meaning of life.

What will the land be used for?— _____.[ ]