HSK 4
打招呼
dǎ zhāohuto greet sb by word or action; to give prior notice
见到邻居要先打招呼。
Jiàn dào lín jū yào xiān dǎ zhāo hu.
Greet your neighbors when you see them.
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Other HSK words sharing a character
Also free:
New in the HSK 3.0 word list at level 4.