重点讲解：
1. to some extent
在某种程度上；
eg. They don't admire his new technique greatly, but they admire it to some extent.
他们虽不十分佩服他的新技术, 但还是多少有点服气。
eg. To some extent, I can understand their attitude.
我在某种程度上是能够理解他们的态度的。
2. on the whole
大体上说；总的说来；
eg. On the whole, I'm in favour of the proposal.
总的说来，我赞成这个提议。
eg. My opinion is on the whole the same as yours.
我的意见大体上同你的差不多。
3. be able to do sth.
能做到…的；
eg. He was able to cast off such an uninteresting task.
他终于摆脱了这么一项乏味的工作。
eg. He was able to fulfil himself through music.
他通过音乐能充分地发挥自己的才能。
