The problem is ________ sometimes when we are given something on a constant bas

题型：不详难度：来源：

The problem is ________ sometimes when we are given something on a constant basis, we start to take them for granted and forget being thankful for what we already have.

A．that	B．how
C．where	D．which

答案

A

解析

A 考察名词性从句。主语是The problem，is是系动词，后面接表语从句。从句中有包含有when引导的时间状语从句，由于从句句意通顺，成分完整，应该使用that引导，that不充当成分，只做引导词。故A正确。