Choose the correct word to make an idiom in each sentence.

1. Lots of people are off sick with the flu in our college. They're dropping like ... .

2. You look a little off ... today. Are you tired?

3. Matt`s really under ... . He`s got a terrible cold.

4. Take it easy for a few days and you'll be back on your ... in no time.

5. You should take some vitamins if you're feeling a bit ... down.