重点讲解：
1. eat off 吃掉；
例句：That day we were so hungry that we ate off a chicken as big as this.
那天我们太饿了，以致于吃了一只这么大的鸡Jqnra#C84=Je+sj。
2. gross out 使(人)作呕；
例句：Mike grossed Sue out when he waved a snake in front of her face.
麦克在苏面前摇一条蛇，使她恶心死了RctbDxg&K|。
4. build up （使）积聚；（使）逐渐增加；
例句：Gradually they will build up a varied, well-balanced vocabulary.
他们将逐步积累起一批内容多样，比例适当的词汇b2@TK0|_jZur。
4. crouch down 蹲；蹲伏；
例句：He crouched down and reached under the mattress.
他蹲下，把手伸到床垫下面q[;kigq[sT3&8iTSe[。