用括号内所给动词的适当形式填空
We are going to do more exercise _________ (keep) fit.
I am going to ___________ (be) a doctor when I grow up.
I’m going to practice __________ (play) the guitar every day.
When did you learn __________ (play) the violin?
—Shall we go to the movies tonight?
—That_________ (sound) interesting.