acute, adapt

acute

In Euclidean [欧几里得] geometry, an angle is the figure [图形] formed by two rays, called the sides of the angle, sharing a common endpoint, called the vertex [边] of the angle. Angles smaller than a right angle [直角] (less than 90°) are called acute angles ("acute" meaning "sharp"). An angle equal to 90° or π/2 radians is called a right angle. Two lines that form a right angle are said to be normal, orthogonal [正交], or perpendicular [垂直]. Angles larger than a right angle and smaller than a straight angle [平角] (between 90° and 180°) are called obtuse angles ("obtuse" meaning "blunt"). An angle equal to 180° or π radians is called a straight angle.

The term normal in mathematics is used in the following broad senses:
1. To denote something upright or perpendicular
2. To denote something that is as it should be. In this sense, normal means good or desirable rather than typical
法线(normal line)指始终垂直于某平面的直线。正态分布(Normal distribution)也叫常态分布或高斯分布(Gaussian distribution)。“学为人师，行为世范”是北京师范大学(Beijing Normal University)的校训，它是启功教授在1996年夏天提出的。法: 标准; 规范。范: 模mú子; 榜样。想当榜样不正直还行？If it's not a right angle, it's an wrong angle.

回忆下力的分解与合成。不正交的两个力，在彼此方向上的分力为0。斜着拉物体，在水平方向上有分力。两个概念正交，大概其就是不搭界的意思。风马牛不相及(出自《左传》)，风x轴、马y轴和牛z轴多欢乐啊。

A reference angle is the acute version of any angle. Both an angle of 150 and 750 degrees have a reference angle of 30 degrees.

The two acute angles in a right triangle are complementary [互余]. supplementary angle: 补角。

An acute triangle (or acute-angled triangle) is a triangle with three acute angles (less than 90°). An obtuse triangle (or obtuse-angled triangle) is a triangle with one obtuse angle (greater than 90°) and two acute angles.

Acute toxicity describes the adverse effects of a substance that result either from a single exposure or from multiple exposures in a short period of time (usually less than 24 hours). Acute toxicity is distinguished from chronic [慢性] toxicity, which describes the adverse [harmful] health effects from repeated exposures, often at lower levels, to a substance over a longer time period (months or years). It is widely considered unethical to use humans as test subjects for acute (or chronic) toxicity research.

汉语有迟钝，敏锐。acute的近义词有quick和smart。“工作好找吗？” 是个尖锐的问题，serious和severe也是acute的近义词。敏锐可以形容感觉，acute可以修饰sense，被锐物扎了都疼啊。

adapt

不是adopt. 变化: adaptable, adaptability, adaptation, adapter/adaptor. 同义词: adjust, alter, change, modify, vary

An adapter or adaptor is a device that converts attributes of one electrical device or system to those of an otherwise incompatible [不兼容的] device or system. Some modify power or signal [信号] attributes, while others merely adapt the physical form of one connector to another.

Many countries with ties to Europe use 230-volt, 50 Hz AC mains electricity, using a variety of power plugs and sockets. A passive electric power adapter, sometimes called a travel plug or travel adapter, allows using a plug from one region with a foreign socket. As other countries supply 120-volt, 60 Hz AC, using a travel adapter in a country with a different supply poses a safety hazard [危险] if the connected device does not support both input voltages.

An AC-to-DC power supply adapts electricity from household mains voltage (either 120 or 230 volts AC) to low-voltage DC suitable for powering consumer electronics. Small, detached power supplies for consumer electronics are called AC adapters, power bricks, or chargers [充电器].

"The screenplay adapter thinks the script needs some work. The plays were a very different story: I worked with the adaptor for 10 drafts." – The Washington Post.

貌似adapter和adaptor都可以指人或物，两者没区别了。老外也有爱较真茴字写法的，而且巨能写。尤其是英语单词长(一维，汉字二维)，洋洋洒洒一大篇。

If you're wondering how to adapt a novel [小说] into a screenplay [剧本], keep reading books. A screenplay or dub [字幕] adaptor — who may not know the source language — will take the script provided by the translator [笔译者] and adapt it for dubbing purposes.