not to refuse

(informal) all right so far, OK, why not?, I can let it pass, that I can tolerate, ... is one thing (but...) (used to say that the first option is (barely) tolerable, but that the second is too much)

(figuratively, informal) not to mince words (to speak abruptly, frankly)

He who says nothing (tacitly) agrees; silence is consent

I don't speak English

(idiomatic) to remain silent

I don't speak French

(vulgar) to do fuck all, not to do a damn thing, to do nothing

(informal, figuratively) for there to be no doubt about it

(informal) to be clueless, to be completely unskilled, not to know what one's doing