1. 一般在名词词尾加-s。如:dog-dogs, house-houses, gram-grams.2. 以-s,-sh, -ch及-x结尾的名词加-es构成其复数形式。如: kiss-kisses, watch-watches, box-boxes, bush-bushes.3. 以-o结尾,注意以下几点:(1)一般在词尾加-es.如:tomato-tomatoes, potato-potatoes(2)如果是外来语或缩写名词, 则加-s。如:piano-pianos, dynamo-dynamos, photo-photos, kimono-kimonos, biro-biros。(3)有些以-o结尾的名词,其-o前是元音字母则加-s。如:studio-studios, radio-radios.(4)以-oo结尾的名词只加-s。如:zoo-zoos。4. 以“辅音字母 + -y“ 结尾的名词,则先把-y改成i,再加-es。如:baby-babies, university-universities, fly-flies, impurity-impurities.5. 下列以f或-fe结尾的名词,须先将-f或-fe改成-v,再加-es。这些名词是:calf, half , knife, leaf, life, loaf, self, sheaf, shelf, thief, wife, wolf 等。如:wife-wives, wolf-wolves, calf-calves.(像roof等词直接加s,如果是初中阶段,掌握roos一个特别单词就行了)6. 以下几个名词scarf, wharf, hoof, handkerchief等的复数形式,可先将-f或-fe改成-v,再加-es;也可直接加-s,即scarfs或scarves, wharfs或wharves, hoofs或hooves, handkerchiefs或handkerchieves。