Coughing _____ also be used for social reasons, such as the coughing before giving a speech．

urse normally attracts 20students per year, ________up to half will be from overseas

Jim，you look sleepy. What’s wrong—I________to write a report last night.

Why didn’t Alex attend the party yesterdayevening—He________not have wanted to see me.

If we are not ________the progress we have made，we will have greater success.