✅ 同义词
🗣️ 情景例句
She's off today.
她今天休假。
An empty bag cannot stand upright.
空袋不能直立。
It was from the study of these that so much was learnt about the interior of the earth.
正是从这两种波的研究中，我们可以了解到地球内部的许多情况。