The Whites were having dinner __(since,when,before,while)(选1）while peter's mother _____(cooked,was cooking),he (anseered,was answering） a telephone from Jack
问题描述：
The Whites were having dinner __(since,when,before,while)(选1）
while peter's mother _____(cooked,was cooking),he (anseered,was answering） a telephone from Jack
答