HSK 7-9
交替
jiāotì动
to replace; alternately; in turn
红绿灯按固定顺序交替闪烁。
Hóng lǜ dēng àn gù dìng shùn xù jiāo tì shǎn shuò.
The traffic lights flash alternately in a fixed sequence.
Say it
Hold the button, say it, then let go.
Other HSK words sharing a character
Also free:
Appears across levels (7-9) in the HSK 3.0 word list.