arc
单词辨析：
指几何学中的弧，也指弧形或弧线。
an arc of 120
º120º的弧
The rainbow formed a beautiful arc in the sky.
虹在天空中形成了一个美丽的弧。
The sun appears to move in an arc across the sky.
看起来太阳在天空中的运行轨迹呈弧形。
指弧形结构的物体。
That arch has a span of 70 metres.
那个拱的跨度为70米。
She was going to visit the Triumphal Arch.
她打算去凯旋门游玩。
指弯曲的形状或呈弓形的物体。
The bow of his lips is very attractive.
他嘴唇的弧形曲线很迷人。
The child wanted to know why the rainbow is in a bow shape.
那个小孩想知道为什么虹为弓形。
含义最广，指任何带有弧度的线条或曲线状物。
The stairs ascended in a graceful curve.
楼梯呈优美的曲线上升。
There is a sharp curve in the road.
路上有个急转弯的地段。
相关例句：
Gaseous helium is used as an inert shielding gas in metal arc and laser welding.
在金属电弧和激光焊接中气态氦用作惰性屏蔽气体。
We studied the natural convection in narrow double-side heating arc by mock-up tests and numerical simulation in this thesis.
本文对双面加热的圆弧形窄缝通道内重水的自然对流进行了模化试验和数值模拟。
Detective and Analytical Systems for the Dynamic Parameters of Arc Welding Process
弧焊过程动态参数的检测和分析系统
Joan of Arc was finally canonized by Pope Benedict XV in 1920.
圣女贞德终于在1920年由教皇本尼狄克十五世封为圣徒。
The background, present achievement and development of low voltage arc fault detection were expounded.
阐述了低压电弧故障检测的研究背景意义、内容成果及发展。
The key factors influencing the secondary arc current and the recovery voltage were researched.
研究了影响潜供电流和恢复电压的关键因素。