C级核心词汇推荐：
breakfast n. 早餐;
breath n. 呼吸；气味(hold one’s breath/屏息; at a breath/一口气);
breathe v. 呼吸;
bridge n. 桥，桥牌(play bridge/打桥牌);
brief adj. 简短的，短暂的（short - brief短暂的）(in brief/简单地说；简明扼要的);
briefly adv. 暂时地，简要地;
bright adj. 明亮的，灿烂的, 聪明的;  (bright – clever – intelligent – smart –wise 聪明的)
brilliant adj. 灿烂的(brilliant - bright)，有才气的；卓越的(brilliant – outstanding卓越的); 
bring v. 拿来，带来，产生；引起( bring about/引起，造成;  bring forward/把……提前；提出;  bring out/使出现， 使显露; bring up/提出；养育);
Britain n. 英国；不列颠(英格兰，威尔士和苏格兰的总称;
British adj. 不列颠的；不列颠人的；英国的；英国人的n. 不列颠人，英国人; 
broad adj. 宽的，广泛的;  (broad –wide宽的)
broadcast n. 广播；播音 v广播播送，播放;
brother n. 兄弟;
budget n. 预算;
build v. 建造，建筑(build up/堆积，逐步建立); (build -- establish建立, 创立)
building n. 建筑物，建筑业;
burn v. 烧，使感觉烧热(burn out/(使)烧坏；烧光；烧尽; burn up/烧完；烧尽；烧光);
burst v. 爆裂，爆发(burst into tears[laughter]/突然大笑[突然大哭]); 
bus n. 公共汽车(take the bus/乘公共汽车; get on[off] a bus/上[下]公共汽车); 
business n. 商业；买卖；交易；生意；事情
busy adj. 忙碌的；热闹的(be busy with [about, in]/忙于; keep sb. busy/不让某人空闲); 
but prep. 除……以外 conj. 而是，但是； adv. 几乎，仅仅(but for/要不是) ; 
buy v. 买; (but – purchase 购买)
by prep. 在附近，在旁边；经，由；依据，按照；通过；用 adv. 通过，经过；附近( by air/railway/sea/plane/bus/乘飞机/火车/船/飞机/公共汽车; pass by/经过；by the rule/按规则; by oneself/单独，独自);
cake n. 蛋糕，饼(a piece of cake/[口]轻松的事，愉快的事); 
calculate v. 计算，考虑(calculate on (upon)/指望着，期待着);  (calculate – count – figure 计算)
call  n.叫声；命令，号召； v. 呼叫；召集；称呼；打电话(call for/需要；要求;  call off/取消; call on/拜访; call for help/呼救; call sb. /叫……；给……打电话);
calm  adj. (天气、海洋等)静的 v. (使)平静，(使)镇定；平息(keep calm!/安静! 保持镇静! calm down/使平息，使平静);