a question about grammar.

hello, i am new to college confidential.

am i on the right section to ask a question? please help me out about a grammar question.

  1. Some critics have argued (1) that Dostoevsky was (2) unique among nineteenth-century authors in that he surrendered fully to his characters and has allowed (3) himself to write in voices other than his own.

this is a problem with verb tense.

the answer is that (3) needs to be changed into allowed. I get it. My question is that can have+pp and past tense be used together? Have+pp is present perfect. it means that it is still in effect. but number 2 and 3 are past. ?? i am getting confused about it.

please help. thanks~

I got it. present perfect is from the past to present… so the past verb can be used in the next sentences.