重点讲解：
1. think highly of 极为（赞许）；（评价）高的；
We all think highly of his research work in this field.
我们对他在这个领域中的研究工作倍加赞赏。
2. grow up 长大成人；成熟；
He'll grow up to be somebody.
他长大了一定能成材。
3. set foot on 踏上，涉足(某地)；
No man has ever set foot on that rocky island; it's impossible to land there.
没人涉足那个岩岛，不可能在那儿上岸。