是a American还是an American

是a American还是an American 用 a American 还是 an American American前面用a还是an American前加a还是an? 是American Chinese还是 Chinese American? ----American boy (a/an/the) She is an A_____ girl.是填America 还是American She is an American girl 还是 She is American girl 应该是are you american还是在american前加an? she is an American.还是she is American American I am an American还是I am an American man那句话对?