As if/ As though

Could you kindly check the correctness of the following sentences?

1)He always talks as though he were a sophisticated person. (Contains present meaning; subjunctive.)
2)That competitor is running so quickly as though he were being chased by a bunch of malicious dogs. (Contains present meaning; subjunctive.)
3)He commanded us as if he were the coach. (Contains past and present meaning; subjunctive.)
4)He taught me as if he had been a teacher. (Contains past meaning; subjunctive.)
5)The weather looks so unpleasant as if it is going to generate a catastrophic hurricane. (Contains present meaning; indicative.)

In fact, I am not quite certain if I should apply "were" to replace "had been" in no.4 or not since it sounds a bit strange with "had been"; however, as far as I know, "were" is a subjunctive form for describing the present, as it is in the second conditional.

Thank you very much indeed.