couple
... preventive adj. 预防的,防止的 couple n. 对;夫妇;数个 blame vt. 责备;归咎于 ...
several
... worth v.值得根据短文内容选择正确答案 several adj.数个 prison n.监狱 ...
a couple of
county 州/郡(相当于我国的县);郡(次于州之行政区) a couple of 两个;数个 Dock (英)船坞;(美)码头 dresser穿衣者,装饰着,碗柜;梳妆台 druggist药剂师;杂货店老板 eggbeater搅蛋机;直升机 ..