1.behavioral a.行为的( of or relating to behavior)
来自behavior(n．行为举止)
例:Geneticists consider the gene to be a behavioral gene.
派生词：behaviourism(n.行为主义)
2.bellows n．风箱(apparatus for driving air into or through sth.)
词根记忆：和bellow(v.吼叫)一起记
3.benchmark n.基准(something that serves as a standard by which others may be measured or judged)；v.标准测试(to study, as a competitors product or business practices, in order to improve the performance of ones own company)
联想记忆：bench（法官席，引申为法律）+mark(记号)一将法律作为我们的基准
例:The technique to judge the performance of a company by comparing it with other companies is called“benchmarking.
4.benefactor n.行善者，捐助者(one that confers a benefit)
词根记忆：bene(好)+fact(做)+or--做好事的人--行善者
例:Since private institutions had also lost benefactors, they began to charge patients.
同根词：benevolent(a．慈善的)
5.beneficiary n．受益人，受惠者(one that benefits from sth.)
词根记忆：来自benefit(n.利益)
例:Moreover, part of this remaining third is received by workers who are shareholders, pension beneficiaries, and the like.
同根词：beneficial(a．受益的，有利的)
6.benefit n.利益，好处(sth. that promotes well-being)；救济金(financial help in time of sickness, old age, or unemployment);v.有益于，对…有益(to be useful or profitable to)
词根记忆：bene(好)+fit--利益；有助于
例:There are no types of vegetation on Tufe lsland that are known to benefit from dry conditions.
同根词：beneficial(a．有益的；有利的)
7.benevolence n.仁慈：善行(an act of kindness)
词根记忆：bene(好)+vol（意志）+ ence--好的意志--仁慈
例:The cult of female domesticity developed independently of the concept of female benevolence.
同根词：benevolent(a.善心的)
8.bestow v.放置(to put in a particular place)；授予(to give)
词根记忆：be+stow(装载；收藏)一收藏起来一放置
例:The committee bestowed an engraved plaque on the contest winner.
9.betrayal n.背叛( defection )
词根记忆：来自betray( v.背叛 )
例:In broadcast debates, critics dismissed the program as a betrayal of national identity.
10.better off a．境况较好或较富裕(be happier or richer)
例:Many of them are no better-off financially than they were before the increase in production.