重点讲解：
1. be laden with
装满的；满载的；
eg. The following summer the peach tree was laden with fruit.
第二年夏天桃树就结满了桃子。
eg. The air was laden with spices - the mingled fragrance of many grasses and flowers.
空气里荡漾着芳香，很多花草混和在一起的芳香。
2. be unique to
独有的；特有的；
eg. No one knows for sure why adolescence is unique to humans.
没有人确切地知道为什么只有人类才会经历青春期。
eg. They are unique to the highlands of Ethiopia.
它们是埃塞俄比亚高地所特有的。
3. be about to do sth.
即将（做…）的；快要（发生…）的；
eg. As she was about to speak, I frowned her down.
她刚要开口，我就皱皱眉示意她别出声。
eg. The makers are about to launch out a new product.
制造商们马上要生产一种新产品。