Zhang Lin was addicted to computer games during his last year in high school , otherwise he         ____________a student of Beijing University .

If you really want yourself to be in good health, you must＿＿＿always＿＿＿so much. 

We __________ so tired. We've only been to a party.

—How about paying a visit to Mr. Richardson, our former history teacher?—Good idea. I will e-mail him today so he ___ know ___ to expect us.

Do you think he is lazy？” “I _____ so once, but I don’t now.”