of no effect 和 of no avail 有什么区别?二者都表示无效,完全无用 如何区别?用法上有区别没?这道题选什么All our efforts to persuade her to come and stay with us were of no___.A.result B.avail C.effect D.purpose

这两个短语用法上有什么区别啊,最好有例句of no effect和to no effect I estimate that this medicine is of no effect. All our efforts are of no effect,为什么要加of? of course no和of corse notA 你旷课了么?B of corse no( not ) no sense of personal no question of take no notice of be of no concern record of no record kinetics of NO no sign of NO.OF BOX: “of no account“ No amount of crying Material of No. have no judge of no solicitation of personnel has no knowledge of