it was in1949()the people'spublic of china was found填什么 为什么
问题描述：
it was in1949()the people'spublic of china was found
填什么 为什么
答
when
时间状语从句
答
that,这里为强调句型，It was......that....强调句时把It was......that....去掉也能组成完整的一句话，整句句子的句意为正是在1949年*建立的
答
应该是这样：
1. it was in 1949 that the PRC was founded. (强调句型，时间前有介词)
2. it was 1949 when the PRC was founded.（时间前没介词）
More example:
it is in this hospital that i was born.
it is this hospital where i was born.
答
that
强调结构句
当被强调部分是状语时只能用that 引导后面的从句
答
that
强调句型 it be.that.