Question

how many pepole are there in shanghai?

Answer 1

B.

1.前面有数字的话,后面紧跟着的hundred,thousand,million,billion都不能是复数.

2.前面没有数字,hundreds,thousands,millions,billions 后面跟 of,解释为“数以百计的”“数以千计的”“上百万的”“几十亿的”