Echelons
n. （机构中的）等级, 阶层( echelon的复数形式 ); （军舰、士兵、飞机等的）梯形编队
🗣️ 情景例句
I visited Japan on an observation tour of its industries.
我到日本观摩它的工业。
Know something like the palm of one's hand.
熟知其事，了如指掌。
When the journalist again failed to reply, the editor reluctantly published the article as it had originally been written.
但记者还是没有回复。编辑无奈，勉强按原样发稿了。