Areopyknometer
[机] 比重瓶比重计
🗣️ 情景例句
Ask Paul Smith to fill in for me.
叫Paul Smith代替我出席。
After my core courses are finished, I'll be doing independent study.
在完成基础课程之后，我将作独立的研究。
He uses a lift to go up and down.
他乘电梯上上下下。