还是 vs 或者
hái shì vs huò zhě
Comparing "haishi" and "huozhe"
Both mean "or": 还是 belongs in questions, 或者 in statements.
还是 in questions · 或者 in statements
How it works
我们明天见还是后天见？明天或者后天都可以。 — Shall we meet tomorrow or the day after? Either works.
The split is clean and mechanical. If the sentence is asking someone to choose, it's 还是; if it's laying out options, it's 或者.
The exception is an embedded question: 我不知道他去还是不去.
Examples
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?
míng tiān huò zhě hòu tiān dōu kě yǐ
明天或者后天都可以。
Tomorrow or the day after both work.
wǒ bù zhī dào tā qù hái shì bú qù
我不知道他去还是不去。
I don't know whether he's going or not.