Peter was so excited he received an invitation from his friend to visit them.A. whereB. t

问题补充：

Peter was so excited he received an invitation from his friend to visit them.

A. where

B. that

C. why

D. when

答案：

A. where

B. that

C. why

(答案→)D. when

解析：考查状语从句。记忆：当他收到朋友要他去看他们的邀请时，Peter是如此的兴奋。句子的when引导的是一个时间状语从句，修饰前面的主句。故D正确。