have some problem doing sth.

have some problems doing sth是对的

省略了(in) doing

类似的结构有：
there be / have some problems(in) doing sth
there be / have some problems with sth

there be / have some difficulty (in) doing sth
there be / have some difficulty with sth

there be / have some trouble (in) doing sth
there be / have some trouble with sth

我是二十多年高三教师，出于某种原因不再教课，但...

We should say \"have some problems (in) doing sth
初二的课本上都有的,介词 in 可以省略 后用doing

have some problem doing sth是单数式 have some problems doing sth是负数形式

在这里problem 是一个象征性的词,代替了问题/麻烦,不用加S的.

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