impact,influence,effect的用法意义区别是什么?

n.结果,效果,作用,影响,(在视听方面给人流下的)印象
vt.招致,实现,达到(目的等)impact
n.碰撞,冲击,冲突,影响,效果
vt.挤入,撞击,压紧,对...发生影响affectvt.影响,感动,侵袭,假装influence
n.影响,感化,*,有影响的人(或事),(电磁)感应
vt.影响,改变
Answer:Affect is a verb that means to have an influence on or to bring about a change in:Does second hand smoke affect the health of all of us?Effect can also function as a verb meaning to execute:Only the president can effect such a change.However,effect is most often used as a noun meaning,result:The drug did not affect the disease,and it had several adverse side effects.Rule of thumb:if you need a verb,nine times out of ten you will used affect; if you need a noun,you will always use effect.
effect有时也可以作动词用,意为“执行”.
例如：Only the president can effect such a change.
但是,effect在大多数情况下都被用作名词,意为“结果”.
例如：The drug did not affect the disease,and it had several adverse side effects.
一个简便的原则就是如果你需要一个动词的话,十之八九选用affect,如果需要一个名词,则通常使用effect.
affect vt.①影响②打动,感动③(疾病)侵袭
词汇辨析affect,effect,influence：
affect常用作动词,effect常用作名词(意为“影响”)：to affect sth.=to have an effect on sth.
effect 作动词时很正式,意为“产生,带来(结果)”,这个产生或带来的结果常常是某人所希望的.
influence指通过行动、榜样等对他人产生潜移默化的影响或作用,注重“影响”的结果.
记忆方法形似词：effect n.影响；effort n.努力
词根记忆af(使)+fect（做）→使人做→影响
effect 43 n.①结果②效果,作用vt.产生,招致
经典例句The effect speaks,the tongue needs not.事实胜于雄辩.
考点提要in effect = in fact 实际上；take effect = come into force 实施,生效；to that effect 大意如此
记忆方法fect(作用)→affect v.影响；effect n.影响
词根记忆ef(出)+fect（做）→做出来→生效,效果