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-You made many mistakes in your writing. If you studied better you wouldn't do.
You have made a lot of mistakes in your writing. If you studied better you wouldn't.You have many mistakes at writing. If you studied better you wouldn't have.![]()
In this case, one should say If you studied better you wouldn't have them. OR If you studied better you wouldn't do. Or If you studied better you wouldn't, shouldn't one?You have many mistakes at writing. If you studied better you wouldn't have.![]()
You have many mistakes at writing.
The first sentence can describe the result, or the first sentence can describe the action:In this case, one should say
Yes, I mean "action".The "at writing" implies action. The lack of any other verb implies "result", because "have" is a main verb.