单词：pencil compass
铅笔圆规
pencil compass的用法和样例：
例句
- Use your compass to bisect an angle.用圆规把一个角二等分。
- Trisecting an arbitrary angle with a compass and straightedge was one of the famous ancient Greeks unsolved construction problems.用直尺和圆规三等分一个任意的角是古希腊著名的构造问题之一。