random
a.任意的，随机的
The company has introduced random drug testing of its employees.公司对雇员进行了随机药物测试。
range
n.一系列;幅度 vi.变动;涉及 vt.排成行
The drug is effective against a range of bacteria.这种药对一类细菌有效。
rank
n.衔;阶层[ pl.]普通成员;排 v.分等级
He held (=had) the rank of Chief Inspector.他的警衔是总督察。
master
n.(男)主人;大师[M-]硕士 vt.精通 a.精通的
a master of disguise伪装高手
mate
n.伙伴，同事;配偶;大副 v.(使)交配
Dad’s office mates are throwing a party for him.爸爸的同事要为他搞个晚会。
