还是
hái shì
Offering choices with "haishi"
还是 is "or" in a question — it asks the listener to pick.
A + 还是 + B ?
How it works
你要喝茶还是咖啡? — tea or coffee? Because 还是 already makes it a question, no 吗 is needed.
In statements, "or" is 或者 instead. Getting this backwards is one of the most common HSK 3 errors.
还是 also means "had better" in suggestions: 你还是别去了.
Examples
nǐ yào hē chá hái shì kā fēi?
你要喝茶还是咖啡？
Would you like tea or coffee?
wǒ men míng tiān jiàn hái shì hòu tiān jiàn?
我们明天见还是后天见？
Shall we meet tomorrow or the day after?
nǐ hái shì bié qù le
你还是别去了。
You'd better not go.
Common mistakes
- Never add 吗 to a 还是 question.