She didn't answer the phone.She ___ be asleep.

This cake is very sweet．You __________ a lot of sugar in it．

But for the help of my English teacher，I________the first prize in the English Writing Competition.

.If you ________ be quiet, I will tell you what happened. 

–Do you know where David is? I couldn’t find him anywhere. – Well. He _____ have gone far — his glasses are still here.