290. lose faith in 对…失去信心
291. on faith 毫无怀疑地, 依赖地
292. faithful to (=loyal to) 对…忠诚
293. fall into the habit (of) 养成…习惯
294. fall short of (=fail to reach a desired result, standard, etc.) 没达到, 低于
295. familiar with 熟悉,了解
296. have a fancy for ( =like sth. without the help of reason) (没有道理地)喜欢, 想要 297. take a fancy to (=become fond of) 喜欢
298. by far 远, 非常 (与比较级或最高级连用)
299. far from 远远不是
300. far from 非但不…(而且)
301. in fashion(=stylish, most modern)时兴,流行
302. after the fashion (of) 依照…
303. find fault with(=complain about; criticize)找毛病，对…吹毛求疵
304. at fault (=in the wrong, blamable)有错
305. in favour of 赞成
306. be in favour with 受宠, 受偏爱;
out of favour with 失宠, 不受宠
307. in one’s favour(=to one’s advantage)对.有利
308. (be) favourable to(=advantageous)有利的
309. fear for (=be afraid for the safety of sb. or sth.) 为…担心
310. for fear of (=in case of; because of anxiety about) 以防, 由于怕
311. in fear of (=afraid for the safety of) 担心
312. feed (sb.) on sth. 靠吃…, 用…喂养
313. be fed up with(=be unhappy, tired about sth. dull) 厌烦, 腻了
314. feel like (=have a desire for) 想要
315. fill in 填写
316. fill out ( =fill in )填写
317. set the world on fire=set the flames on fire(=do sth. remarkable)有突出成就 318. play with fire (=take great risks)干冒险事
319. set sth. on fire(=set fire to sth.)使..着火,放火
320. at first sight(=when first seen)乍一看,一见
321. for the first time 第一次 (作状语)
322. in the first place 首先, 第一
323. fit into 刚好放入
324. fit in with ( = suit , fall into agreement) 合适, 相配, 一致
325. (be) fit for (=right and suitable for) 适合
326. focus on (=concentrate on) 集中在…上
focus sth. on 把…集中在…上
327. be fond of 喜欢
328. (be) in force 有效 , 实施
329. go into force 开始生效
330. by force 靠武力, 强行
331. force…on 把…强加给…