Question

It is well-known ______ a person, especially the old, eats too much he’ll feel uncomfortable.

A．that

B．when if

C．if

D．that when

Answer 1

D

考查：it做形式主语，真正地主语是后面的that 从句，that 从句中又是一个由when引导的时间状语从句。句意：众所周知。当一个人，尤其是老人，吃太多的时候他会感到不舒服的。故选D。