Peter ________ be really difficult at times even though he's a nice person in general.

It is reported that by careful questioning the police managed to _________ the information they were looking for.

This book_______ 10 units , _______ two revision units.

 - The water was left running all night long.- Yes. It seemed that John ___. He was the last one to leave the lab.

—Next week I will go to a job interview．Will you give me some suggestions?—Smiling is a great way to make yourself      ．