重点讲解：
1. a quarter of
四分之一；
eg. A quarter of all the people surveyed were don't-knows.
参加问卷调查的所有人中有四分之一没有表示明确意见。
eg. They walked a quarter of a mile down the mountainside.
他们沿山坡下行了四分之一英里的路程。
2. be home to sb./sth.
是……的发源地，是……栖息地，是……的家园；
eg. Its neglected state might make it seem as though it were abandoned, but it is home to an old man and a jack-in-the-box.
不为人知的状态似乎表明这座房子已经被遗弃了，但是它却是一位老者和一个玩偶的家。
eg. She said that the British Library is home to the whole of the English language memory since the English word began.
大英图书馆的藏书包罗万象，囊括了自英语产生以来的所有英文书籍。
3. help to do sth.
有助于做某事；帮忙做某事；
eg. Attractive packaging can help to sell products.
精美的包装有助于产品的销售。
eg. The music will help to relax you.
音乐会使你感到轻松。