重点讲解：
1. fence off (用围栏、篱笆等)将(一块地)围起来；
When she and Luther got their house, they would fence off a lawn and raise roses from cuttings.
等她和卢瑟有了自己的房子，他们就会围起一块草坪扦插玫瑰lz)P&rx,#F06BD。
2. dry up (使)枯萎；(使)干透；
As the day goes on, the pollen dries up and becomes hard.
日子一天天过去，花粉干结成了硬块o#)Kj)*e6v8SClF。
3. be composed of 组成；构成；
A methane molecule is composed of one carbon atom attached to four hydrogens.
甲烷分子由1个碳原子与4个氢原子构成h&Bo@s)Mji+;PeJ3。
4. be dependent on 依靠的；依赖的；
You can't be dependent on your parents all your life.
你不可能一辈子靠父母生活kZ]m2V!;bVz@m。