Mr. Li can’t attend the meeting on time _____ he takes the early flight to get there.
A. because B. whenever C. if D. unless
I ____ my pen on the table, so I can’t write down his telephone number.
A. leave B. forget C. have left D. has forgotten
—I went to your house last night, but no one was in.
—I ____ speaking English with my friends in the school at that time .
A. practiced B. was practicing
C. have practiced D. am practicing
Our classroom ___ every day. We can study comfortably in it.
A. cleans B. clean C. was cleaned D. is cleaned
—Must I go out with him?
—No, you _____ .
A. needn’t B. mustn’t C. can’t D. couldn’t
Talking about problems is better than keeping them as ______.
A. talks B. thoughts C. secrets D. speeches