这个搜索引擎的爬虫每天会扫描数百万个网页。

The search engine's ___crawler scans millions of web pages every day.

这台履带式拖拉机非常适合在松软的农田里工作。

This ___crawler tractor works perfectly in the soft farmland.

这个爬行的小家伙正在地板上追逐他的玩具车。

The little ___crawler is chasing his toy car on the floor.