例句與造句

1. If this screw motion has zero pitch then the trajectories trace circles, and the movement is a pure rotation.
2. "We have no jobs, no money from the Palestinian authority, no future, no anything, " said Haitham Karaja, tracing circles in the dirt with a sandaled foot.
3. It's difficult to find tracing circle in a sentence. 用tracing circle造句挺難的