In English we use I don´t think + verb (affirmative). Let´s have a look at these sentences.

Incorrect: I think it´s not going to rain.
Correct: I don´t think it is going to rain.

Incorrect: I think you shouldn´t go out tonight.
Correct: I don´t think you should go out tonight

Remember we say…

Affirmative: I think so
Negative: I don´t think so (I think no)

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