R factors
[医] R因子, 叶酸
🧩 词语组成解析
n. 因素（factor的复数）
🗣️ 情景例句
a game which I brought home to study.
我带回来研究的游戏。
He insisted that he was innocent.
他坚称自己是无辜的。
What was the population of the more developed countries in 1950?
1950年较发达国家的人口是多少？