Back-scratching
n. 互相利用
🧩 词语组成解析
back
[bæk]
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;
v. 擦伤；划伤；刮痕（scratch的ing形式）
🗣️ 情景例句
But first in the school-rooms.
但首先是在教室 。
Is that a car?
那是一辆小汽车吗？
Up to now, historians have assumed that calendars came into being with the advent of agriculture, for then man was faced with a real need to understand something about the seasons.
历史学家迄今认为日历是随农业的问世而出现的，因为当时人们面临着了解四季的实际需要，