当你早上遇见老师的时候,你应该说________。
---Have you seen him recently? ---Yes. I him the other day on the street.
To our _________, Hawking didn’t worry about his problems in the slightest, _________, he just face the problems.
It is our duty ______much attention to ________ our best to keep our city clean.
If I were you, I’d talk ______someone ______looks friendly.
It took him morning to check outinformation.