safe [sef] 词频1 词根: 服侍

adj. 安全的;保险的，肯定的;无损的;提供保护的; n. 保险箱，保险柜;冷藏箱;〈俚〉避孕套;

💡 被save（拯救）已safe（安全）

"The family jewels are locked away in a safe."

近义：strongbox, vault, innocuous, inoffensive, offenceless, riskless 反义：hesitant, hesitative, infirm, irresolute, shaky, skeptical

trip [trɪp] 词频1 词根: tr-

n. 旅游，出行;摔倒，绊倒;绊（使某人跌倒的动作）;错误，过失; vi. 绊倒，绊;旅行;轻快地走，跳; vt. 使犯错误;松开（离合器等）以开动;

"His wife accompanied him on the trip."

近义：lurch, stumble, wallop, wobble, bumble, bump

back [bæk] 词频1

n. 背，背部;背面，反面;后面，后部;（椅子等的）靠背; vt. 使后退;支持;加背书于;下赌注于; vi. 后退;倒退; adj. 背部的;后面的;以前的;拖欠的; adv. 以前;向后地;

"Water allotments to farmers were cut back in the drought."

近义：second, support, endorse, illustrate, document, backtrack 反义：impel, inch, save, loop, sheer, slew