once [wʌns] 词频1

adv. 一次，一趟;一倍;曾经;一旦; conj. 一旦…就…;一经; n. 一次，一回;

💡 on=one一+ce次 → 一次

"Once in the bloodstream, the bacteria adhere to the surface of the red cells."

近义：heretofore, occasionally, onetime, previously, sometimes, thereinbefore

continue [kən'tɪnju] 词频1 词根: con

vi. 持续;逗留;维持原状; vt. 延期;使延伸;使持续;继续说;

💡 con全部+tinu握住+e→全部拿住→做事做到尾→继续

"The President was given a blank check by Congress to continue the war."

近义：insist, keep, persevere, persist, proceed, prosecute 反义：quit, stop, leave, desist, cut, finish

begin [bɪ'ɡɪn] 词频1

vt.& vi. 开始;着手;创始;创办; vi. （从…）开始;起始;起初是;开始讲话;

"There is growing apprehension that fighting will begin again."

近义：induct, initiate, launch, originate, spark, start 反义：realize, stop, terminate, accomplish, clinch, close

must [mʌst] 词频1

aux. 必须;必然要;（做出逻辑推断）;（表示坚持）; n. 必须做的事，必不可少的事物;葡萄汁;霉臭;麝香; vt.& vi. （表示必要或很重要）必须;（提出建议）应该;得;（表示很可能或符合逻辑）一定; adj. 不可或缺的;狂暴的;

"You must be able to speak French for this job."

近义：ought, should, necessaries, necessity, precondition, prerequisite