叛乱分子用捡来的零件组装了一个粗糙的爆炸装置。

The rebels assembled a ___crude explosive device from scavenged parts.

根据他粗略的草图，我们几乎无法理解提议的布局。

Based on his ___crude sketch, we could barely understand the proposed layout.

早期人类使用粗糙的石制工具进行狩猎和切割。

Early humans used ___crude stone tools for hunting and cutting.