重点讲解：
1. go down （价格、水平或数量）下降，下跌；
Crime has gone down 70 percent.
犯罪率下降了70%OZ[Zb]Ip|zUY&iwc。
2. in time for 及时；不迟；
I arrived just in time for my flight to London.
我及时赶上了飞往伦敦的航班(fKycUETr7gWnM;wLC。
3. lock away 把…锁起妥藏；
She meticulously cleaned the gun and locked it away in its case.
她小心翼翼地把枪擦拭干净，放进枪盒里锁好0H=vNgx;)xulu@MT。
4. be prone to 有（不好的）倾向的；易于…的；很可能…的；
For all her experience, she was still prone to nerves.
尽管有经验，她还是容易紧张|K0LSiZ,mTeBg;。