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……
332.in the form of以……形式
333.be fortunate in幸运，有好运气
334.free of charge免费
335.be freed from免受，没有……
336.in front of在……前面 in the front of在……前部
337.furnish……with (=supply)向……提供
338.in general (=in most cases， usually)通常
339.catch (or get) a glimpse of瞥见(强调结果) take a glance (or look) at看……眼(强调动作)
340.be good for对……有好处;对……有作用 be good at擅长于;be good to对……好
341.in good time (=early)早早地(做完，到达等)
342.for good (=for ever)永远地，长期地
343.take……for granted (=assume to be true)把……认为理所当然的
344.be grateful to sb. for sth.因……感谢某人
345.on the ground(s) of (=because of) 由于……
346.fall to the ground(计划，希望等)失败，落空
347.on one‘s guard (against) 谨防，警惕 (be)on guard站岗
348.guard against (=defend，keep safe) 警惕，防止guard……against警卫……防止
349.guess at猜，估计
350.by guess靠猜