Daniel is busy these days. I doubt     he will come to my birthday party or not this Sunday.

--Now most teenagers write to each other not by letter ________online.
--Yes, the Internet has become a part of their life.

—Our head teacher says we should have more sleep these days.
—I don’t agree with his idea __________ he might be right.

— Amanda, hurry up! The bus is coming!
— Oh, no. We mustn’t cross the street        the traffic lights turn green.

 My friend’s plane had taken off　　　 I got to the airport to see him off.

We started climbing the hill in the early morning 　　　 we could watch the sunrise.

Put on your coat,        you will catch a cold.

Study hard, ______ you’ll pass the exam.

_________ I could think of an answer, the teacher asked someone else.

You’d better finish your homework now,         I won’t let you out.
A. and                  B. or                   C. so