词汇和语法归纳(对照中文解释)
41.take off 起飞/脱下
42.east/west/south/north/eastern/western/southern/northern 东南西北
43.sth is worth doing 某事值得做
44.sth needs doing/sth needs to be done 某事需要做
45.in case 万一/以防
46.not…until… 直到……才
47.unless/if…not… 除非;如果不
48.关联连词(主谓一致的就近原则)
49.prevent/keep/stop sb from doing sth 阻止某人做某事
50.the+比较级， the+比较级 越……越