1.could you please tell me if Jack ----us?

1.could you please tell me if Jack ----us?
will join / join
2.I am surprised that you can buy such a good car with--- little money?
such/so 可以用such吗 这里后面跟的是不可数名词啊~
3.CHINA did not win a lot of medals ----these winter games.
on/at
4,----to enjoy everything in our daily life,you will be happy.
try/trying
5,It is likely to leave you thirsty.
leave likely
6.think twice before you give your child an unual name.
think twice twice这里是什么语法现象.