动词变名词1.在词尾加er,r ,双写加er 或or:A. play _ player, sing _ singer, wait _ waiter , find _ finder,thrill _ thrillerB. write _ writer, drive _ driver, come _ comer, explore _ explorerdance _ dancerC. run _ runner, win _ winner, rob _ robber, traval _ travallerD. visit _ visitor, invent _ inventor2. 在词尾加ing:build _ building, draw _ drawing, end _ ending, begin _ beginning,swim _ swimming， skate _ skating, feel _ feeling, say _ saying,mean _ meaning, cross _ crossi
