1.
A rail or set of parallel rails upon which railroad cars or other vehicles run.
铁轨铁路车厢或其它车辆可在上运行的一条或一套平行轨道
2.
conductor rail (raillaid parallel to the tracks)from which a railway locomotive picks up electric current
导电轨（与路轨平行的轨道,可供机车导入电流）.
3.
First, we know that the planets all orbit close to the earth's orbital plane, the ecliptic.
首先，我们知道所有行星的轨道都很靠近地球的轨道平面――黄道面。
4.
a pair of parallel rails providing a runway for wheels.
一种为铁路提供跑道的平行铁轨。
5.
Design of the Level Moving Machinery for S/R Machine;
有轨巷道堆垛机水平运行机构的设计
6.
Not running on tracks or rails.
无轨的不在轨道或铁轨上运行的
7.
Planets roll on their courses.
行星在轨道上运行。
8.
biting stabilized platform
侦察用轨道式稳定平台
9.
The act or process of going out of orbit.
脱离轨道脱离轨道的行为或过程
10.
and welded rails have begun to replace jointed rail. all these developments permit higher speeds and a smoother ride.
焊接轨道已开始代替有接头的轨道。所有这些技术使火车的速度更快，行驶更平稳。
11.
Simulation of the Electric Particle's Closed Orbits in Parallel Electric and Magnetic Fields near the Elastic Surfaces
带电粒子在平行电场和磁场及弹性界面附近闭合轨道的模拟
12.
intraplanetary space
行星轨道与太阳间空间
13.
lunar orbiter spacecraft
月球轨道宇宙飞行器
14.
Trains run on a railway track.
火车在铁路轨道上行驶。
15.
circum earth orbit
地球卫星的环行轨道
16.
OVM (Orbiting Velocity Meter)
沿轨道运行速度测量器
17.
Will it be on the right course?
飞行轨道是否正确？
18.
he plotted the orbit of the moon.
她画出了月球运行轨道。