she has to do some exercise to stay healthy.

问题描述:

she has to do some exercise to stay healthy.
she doesn't ____ to do _____ exercise to stay healthy.否定句我填的是have 和any 但为什么答案却是have 和 some.不是some 用于肯定句中?any 由于否定句中?

一般规则是:some 用于肯定句中,any 由于否定句中,但在固定词组中可以不改