Pentavalency
五价
🗣️ 情景例句
There's nothing more joyous than the arrival of a new baby.
没有任何事能比新生儿的到来更令人喜悦的了。
In elementary school,the child learns to read and write.
在小学，孩子学习读写。
The other students in the class keep their eyes closed.
班里其余学生一直闭着眼。