Principal optic axis

principal ['prɪnsəpl]

adj. 最重要的;主要的;资本的;本金的; n. 首长，负责人;主要演员，主角;[法]委托人，当事人;本金;

prin主要的+cip拿，抓，握住+al形容词后缀 → 主要的；首要的

optic ['ɔptik]

adj. 眼睛的，视觉的;光学的;镜片;

axis ['æksɪs]

n. 轴，轴线;[政]轴心;轴心国;[植]茎轴;

axi-, axl- 轴

He treats everyone with courtesy.

他对待每一个人都很有礼貌。

I lift weights all day long. I can't think but that I'm healthy.

我一整天都在举重，健康至上嘛。

OK, everyone. Less noise, please! Gather round and listen carefully. First we are going to search the beach and the rock pools. Let me remind you what we are looking for: seaweeds, fish, plants, all living things. When you find anything, make a note where

00在这里集合，游泳之后再吃午餐。别着急！我们有足够的时间。