cavities

这组词都有“洞”“孔”“穴”的意思。它们的区别在于:hole指任何物体中的开口、穿孔或洞穴; cave指山洞、洞穴或地窖; cavity是科技术语或专门用语,只指坚硬物体上的洞穴,通常表面有开口可见。例如:

The men have dug a hole in the road.那些人在路上挖了一个洞。

The cliff dwellers found that natural caves gave them warmth and protection during the Ice Age.悬岩洞人发现在冰河时代天然的洞穴不仅温暖,还能借以自卫。

The pleural cavity is a body where the lungs are situated.胸膜腔是人体内肺脏所在的地方。