mad adj. mentally ill 发疯的,狂 热的
词组 go mad 发疯; be mad at somebody 生…的气;
be mad at / about 为…生气/迷上; drive someone mad;
maintain vt. keep up, retain, continue 维持,建立
词组 maintain life维持生命 maintain friendship 保持友谊
maintain peace 维持和平 maintain a big family 养活一大家子人
maintain roads 养路 maintain that 坚持认为…
Nowadays it is becoming more and more difficult to maintain a car as the oil prices go up sharply.
major adj. greater or more important 主要的，重大的，主修的
