this is ____UFO A.a B.an C.the

this is ____UFO A.a B.an C.the 1、Two fishermen said they had ever seen ____UFO.a.the b./c.a This is ( )orange car. A.a B.an C.the This is a book ( )and book is new A.an B.a C.the D./ this is ___flat .it's ___American fiat A.a,the B.a,an C.the, is this ____ tape player?yes,it is a.a b.an c.the d./ 单项选择 What is this,plese?---It is UFO.A.a B.an C.the D\ This is a ( ) useful advice A a B an C the D 应选哪一个 There is [ ] 'm' in the word 'map' A.the B.a C.an D this 说清楚 This is ( ) orange flower A a B big C an where is ( ) alarm clock?A an B a C the D this 英语选择90.This is not __________ medicine I need.A.a B.an C.the