87.they didn't resolved yet（他们至今还没有答案）
这句是可以的
88.What most parents cared about（大多数父母所关心的）
也可以,改一下most of parents
Most ofparents cared about
89.in case of the low temperature（以防天气变冷）
这句不太好
in case the weather become cold
90 decide start their own business（决定自己创业）
创业,用carve out ,decide+to
decide to carve out by oneself
91.untill a doctor
find it out ocassionally （知道一名医生发现它）
这里不用find out,find out 一般是泛指,是看不见,摸不着的,例如：真理
untill a doctor found it比较好