第 1 题 · 四级
Sugar is soluble in water, which the experiment clearly showed.
核心词：soluble ˈsɒljəbl adj. 可溶的
糖可溶于水，实验清楚地显示了这一点。
一般现在时主系表 + 介词短语 + which 从句短语 be soluble in短语 water-soluble
Sugar is ___ in water, which the experiment clearly showed.
第 2 题 · 四级
The actor waited for his cue, which the director gave with a nod.
核心词：cue kjuː n. 提示，暗示
演员等待入场提示，导演点头示意。
一般过去时wait for + which 从句短语 wait for the cue短语 on cue
The actor waited for his ___, which the director gave with a nod.
第 3 题 · 四级
The children hid in a hollow tree, which nobody could find easily.
核心词：hollow ˈhɒləʊ adj. 中空的，空的
孩子们躲在一棵空心树里，没人能轻易找到他们。
一般过去时主谓 + 介词短语 + which 从句（情态否定）短语 a hollow tree短语 a hollow sound
The children hid in a ___ tree, which nobody could find easily.
