– Whose ping pong bat is this? -- I’m not sure. I think it ______be Tom’s.

— I phoned you yesterday morning. A girl answered, but I didn’t recognize the voice.— Oh, it ____ my younger sister. She was in my room at that moment.

Something terrible _________ if he didn’t come to the bar as he always did.

 My sister met him at the street yesterday afternoon, so he __________ your lecture.

----Will Barbara come to our party? ----I am not sure, because he ____ go to the concert with his friend.