第 1 题 · 高考
The physicist explained the theory, which was too difficult for us to understand.
核心词：physicist ˈfɪzɪsɪst n. 物理学家
物理学家解释了那个理论，对我们来说太难懂了。
一般过去时too...to + which 定语从句短语 a physicist短语 physics
The ___ explained the theory, which was too difficult for us to understand.
第 2 题 · 高考
The explorer crossed the desert alone, which was a very dangerous journey.
核心词：explorer ɪkˈsplɔːrə n. 探险家
探险家独自穿越沙漠，这是一次非常危险的旅程。
一般过去时which 非限制性定语从句短语 an explorer短语 explore the world
The ___ crossed the desert alone, which was a very dangerous journey.
第 3 题 · 高考
Boxing requires great strength and skill, which is why it is a hard sport.
核心词：boxing ˈbɒksɪŋ n. 拳击
拳击需要极大的力量和技巧，所以是一项艰难的运动。
一般现在时动名词主语 + which is why短语 boxing短语 a boxing match
___ requires great strength and skill, which is why it is a hard sport.
