他启动了拖拉机。

He started up the ___tractor.

曾经从事传统耕作的农民现在正在引进拖拉机等机械。

Farmers who used to practice traditional farming are now introducing machinery such as ___tractors.

一台强大的拖拉机对于大规模农业操作至关重要。

A powerful ___tractor is essential for large-scale farming operations.