The students are warned not to talk about anything ______ to the accident that happened the other day in the school.

The instructor asked us to list anything in our past that we felt ______ of，regretted and read our lists aloud.

Though my grandfather is in his eighties, he is still as _________ as a young man and hates sitting around doing nothing all day.

You can see the stars on a clear night，but in the daytime theyare _______.

The employees were tired of working ______ hours and some of them even gave up their work.