____ can come in. I’m too busy to see ____. —Ok, I know.

Let the dog loose so that it_____have arun

It was too dark, and I couldn’t _______ thewords written on the blackboard.

(2013·北京东城区高三教学统一检测)In his speech, he said that it was his primary school teachers that he was fond of ________ influenced his whole life.

Scientists are convinced ________ the positive effectof laughter ________ physical and mental health