11.The reverse is also true:反之亦然
12.Tie up with/busy with
13.Tired of/get bored of
14.Under the weather:身体不舒服
15.Well-off/rich people
16.White elephant:无价值的东西，废物
17.White lie:善意的谎言
18.You bet :当然
19.Take one’s time;从容不迫
20.Take one’s word:./believe in sb./trust sb.