Forty (year) development has changed Huai'an into a modern city.
It is very important for children (learn) how to do chores at home.
Could you please tell (he) to call me back?
Sure, no problem.
If he (go) to the party, he'll have a good time.
There (be) a book and two rulers on the desk.
Teenagers should (allow) to choose their own clothes.