【词汇讲解】
1.crust n. 外壳，坚硬的外壳，面包皮
如：The earth's crust is layered..
地球的外壳是分层的。
The crust on the snow was thick enough for us to walk on it.
外层的雪已经冻硬，可以在上面行走。
The snow crusted the lake last night.
昨夜的雪使湖面结了冰。
2.tablespoon n. 汤匙，一汤匙容量
如：Add one level (ie not heaped) tablespoon of sugar.
加一平餐匙糖。
3.stir vt. 激起，惹起，搅和
如：The news caused quite a stir in the village.
那消息在村里引起了一片混乱。
Old memories stirred as she looked at the photographs.
她看到这些照片，唤起了对往事的回忆。
There was a stir of excitement as she entered the theatre.
她一走进剧院就引起了一阵兴奋。
4.mixture n. 混合，混合物
如：Do you know the constituents of the mixture?
你知道这种混合物的成份吗？
This is a mixture of the best tobacco.
这是由最好的烟叶配制成的。