@Qin Chen: Ms. Qin, in English we often have rules that apply to some moods (such as questions or negatives, the interrogative and negative moods) but not statements (i.e. the indicative mood). In this case, we use ‘ever’ with the present perfect in questions (e.g. Have you ever had hot pot?) and negatives (e.g. I’ve never, ever tried that. ‘Never’ is in fact a negative form of ‘ever’.), but not with statements. We would write, “I’ve eaten stinky tofu before, ” without ‘ever’.

However, in Mandarin, the experiential aspect marker, 过/-guo, is not restricted to certain moods. It must be used in statements, questions, and negatives.

Just remember that ‘ever’ is not a 1:1 exact translation of 过/-guo. 过/-guo is a grammatical suffix that is required; ‘ever’ is an optional adverb.