HSK 4
用于
yòngyú动
to use in; to use on; to use for
这间教室用于音乐课。
Zhè jiān jiào shì yòng yú yīn yuè kè.
This classroom is used for music classes.
Say it
Hold the button, say it, then let go.
Other HSK words sharing a character
Also free:
New in the HSK 3.0 word list at level 4.