Please give me envelope I want to write a letter to my father.A. aB. anC. theD. /

问题补充：

Please give me envelope, I want to write a letter to my father.

A. a

B. an

C. the

D. /

答案：

A. a

(答案→)B. an

C. the

D. /

解析：句意：请给我一个信封，我想给我的父亲写封信。结合语境可知前文泛指任何一个信封，故用不定冠词。Envelope词首音素是元音，故不定冠词用an，选B。