In Present perfect^x, Stative verbs^x

Hi, paco! I see.... Actually I did not pay much attention to the word "until". You've explained my problem very clearly, with regard to Q1. I really appreciate your kindness. But let me put my question in this way. You say: there seems to be some contradiction in the sentence . Normal...

Hello Roro As you know I'm an English learner and I myself am not so confident about between the simple tense and the progressive tense. So please use the following as something like junk food for your thought until native speakers give you more decisive answers. Q.1) I think you should change...

Neither of your natural-sounding examples has an indefinite article followed by a time unit followed by "before" within an "if" clause. It seems to me that one or more of these factors must be contributing to the difference we sense. "I think we have met before" has no article and time unit, so...