请仔细阅读我所写疑问及提示要求①

①打括号(in)要也行不要也行,这是我问老师的,但问题是我弄不明白既要要也行不要也行,那么去掉又是肯定吗,不去掉又是否定吗?那么有时候去掉又怕还是否定,不去掉又怕还是肯定,我难以区别开来,请老师为我很好分析及解释举倒,只针对打(in)在in外面打括号这种问题?图片已发来请看!

解题思路： 同学你好对于 “做某事有困难”这个词组中的介词in在使用时可有可没有， 而我们平常使用时经常是把介词in省略掉的， 当然带上in也没有错误， 例如： I have trouble/difficulty/problems/have a hard time in finding your house=I have trouble/difficulty/problems/have a hard time finding your house 类似短语还有： be busy (in) doing sth 忙于做某事 be late (in) doing sth 做某事做晚了或做迟了 spend money [time] (in) doing sth 花钱(时间)做某事 waste money [time] (in) doing sth 浪费钱(时间)做某事 have luck (in) doing sth 做某事时有运气(走运) have difficulty (in) doing sth 做某事有困难 have trouble (in) doing sth做某事有困难 have both
解题过程：
同学你好对于 “做某事有困难”这个词组中的介词in在使用时可有可没有， 而我们平常使用时经常是把介词in省略掉的， 当然带上in也没有错误， 例如： I have trouble/difficulty/problems/have a hard time in finding your house=I have trouble/difficulty/problems/have a hard time finding your house。
类似短语还有：
be busy (in) doing sth 忙于做某事
be late (in) doing sth 做某事做晚了或做迟了
spend money [time] (in) doing sth 花钱(时间)做某事
waste money [time] (in) doing sth 浪费钱(时间)做某事
have luck (in) doing sth 做某事时有运气(走运)
have difficulty (in) doing sth 做某事有困难
have trouble (in) doing sth做某事有困难
have bother (in) doing sth 做某事费劲
have a problem (in) doing sth做某事有困难
have a good time (in) doing sth 做某事很开心
have a hard time (in) doing sth 做某事很辛劳
find difficulty (in) doing sth 做某事发现有困难
There is no difficulty (in) doing sth 做某事没有困难
There is no use (in) doing sth 做某事没有用
There is no point (in) doing sth 做某事没有意义