doubt [daʊt] 词频1 词根: dou

n. 怀疑，疑虑;未确定; vt. 怀疑，疑惑; vi. 不确定，不能肯定或怀疑;

💡 doubt二→二种状态→怀疑

"a feeling of doubt and uncertainty"

近义：disbelieve, hesitation, hesitate, mistrust, question, stagger 反义：prove, reassure, verify, vouch, check, demonstrate

supposed [sə'pəuzd] 词频2

adj. （按规定、法律、协议等）（不）应当;假定的;（只用于否定句）不准;（对某人所说的话表示气愤或不大理解）那是什么意思; v. 料想( suppose的过去式和过去分词);意味着;[用于被动语态]认为应该;[用于祈使句]让;

"Am I supposed to finish the homework today?"

近义：hypothetical, imaginary, assumed, assumptive, notional, phony 反义：legitimate, original, authentic, real, sterling, truthful

start [stɑrt] 词频1

n. 开始;动身;开动;起点; vt.& vi. 出发，启程; vt. 起动;提出（问题）;开办;使开始; vi. 起始;突然出现;突然跳起;突然涌出;

"The students return in October for the start of the new academic year."

近义：begin, commence, open, implement, induct, initiate 反义：realize, stop, terminate, accomplish, clinch, close

sharp [ʃɑ:p] 词频1 词根: sh-

adj. 敏锐的;锋利的;狡猾的，聪明的;尖锐的; adv. 猛烈地;尖锐地;尖利地;偏高地; n. 升半音;尖头;骗子;内行，专家; vt. [音乐]把（音调）升高（半音）; vi. [音乐]升音演奏（或演唱）;

"Watch out for sharp bends and adjust your speed accordingly."

近义：incisive, incisor, jagged, keen, peaked, penetrating 反义：obtuse, contusive, dull, dulled, edgeless, idiotic