材料：A Brief HIstory of Time-- Chapter 2
1.elliptical：having an oval shape (adj)
(n) ellipse= an oval
2.spiral
3. take up （intransive）= continue
原句：any body would take up if it were not driven by some force.
4.hold
(idm 习语)hold `goodremain true or valid 仍然适用; 仍然有效
原句:if one carried out experiments with moving bodies on the train, all Newton's laws would still hold.
5.stub
~ sth (against/on sth):strike (esp one's toe) accidentally against sth hard 使（尤指脚趾）碰到某物
eg: I've stubbed my toe on a rock.我的脚趾碰到石头上了.
6.separate from= independant of 尤其是后者可能想不起来用
7.propagation可以表示观点（抽象）和光（具体）的传播
propagation of light
8.crest
the top or highest part of something such as a wave or a hill
wave crest:波峰
9.infrared adj 红外线
a type of light that feels warm but cannot be seen
10. ether=aether: upper sky
11.postulate
n thing assumed to be true, or accepted as a basis for reasoningor calculation 假定; 假设; 公设
12.pulse n.
single vibration of sound, light, electric current, etc （声波﹑ 光波﹑ 电流等的）一次脉动
也表示脉搏，所以诊脉的表达是take/feel one's pulse
13.cesium
某种化学元素
14,.coordinate n.
either of two numbers or letters used to fix the position of a point on a graph
or map 坐标
15.Piccadilly Circus
Piccadilly Circusis a famous traffic intersection and public space of London's West End in the City of Westminster.
16.Alpha Centauri
半人马座阿尔法星
17.emit v.
give or send (sth) out; discharge 发出光和热
18.radius
19.warp v.
=bend
curved、warped其实是近义词
20.curvature n.
n [U] curved form; curving 弯曲形状; 弯曲:the curvature of the earth's surface地球表面的曲度
