Fill in the blanks using the following expressions.
1. all of whom
2. give up
3. waned
4. tried
5. to

1. He has dedicated his life ___ scientific research.
2. He counselled them to ___ the plan.
3. She ___ various remedies, but none of them worked.
4. Sarah has four sons, ___ have autism.
5. Their popularity ___ during that period.

The answer key
1. to
2. give up
3. tried
4. all of whom
5. waned