Chinese Grammar learning 语法: 到底

到底 (dàodǐ) literally means "to the bottom", and often is used wher the speaker wants to get to the bottom of a problem or issue, emphasizing or questioning what the real reason for something is.

到底 as 毕竟 or "in the end"

It is often used like 毕竟, to mean "after all" or "in the end". When used in this way, 到底 is used to emphasize a reason or characteristic the speaker considers to be most important.

Basic Structure 1

到底 + reason/characteristic
Examples

tā dàodǐ shì ɡè dà láobǎn, chūshǒu hěn dàfānɡ.
他 到底 是 个 大 老板，出手 很 大方 。

("He is a high-level boss, after all...")

tā dàodǐ shì ɡè ɡāoshǒu，nǐ hěn nán ɡēn tā bǐ !
他 到底 是 个 高手，你 很 难 跟 他 比 !

("He is a master, after all...")

Basic Structure 2

虽然 + A + 但 + 到底 + B + C

In this structure, A and B are reasons or characteristics, and C is a result or conclusion.

Examples

suīrán fánɡzi hěn xiǎo, dàn dàodǐ shì zìjǐ jiā, zhù zhe shūfu.
虽然 房子 很 小，但 到底 是 自己 家，住 着 舒服 。

Even though the apartment is small, and just for one person after all, it's still comfortable.

suīrán tā zuòcuò le shìqínɡ，dànshì tā dàodǐ háishì ɡè xiǎoháiér，nǐ jiù bié dǎ tā le。
虽然 他 做错 了 事情，但是 他 到底 还是 个 小孩儿，你 就 别 打 他 了。

Although he's done bad things, he is only a child after all, so don't hit him.

到底 as 究竟 or "on earth"

到底 can be used to mean "on earth", wher it is used to emphasize a question. In this sense, 到底 is similar to 究竟.
Basic Structure

到底+question phrase

Examples

nǐ dàodǐ zěnme le？
你 到底 怎么 了？

What on earth is up with you?

dàodǐ zěnme zǒu？
到底 怎么 走？

How on earth do we get there?

nèijiān dàodǐ shì shuí？
内奸 到底 是 谁？

Who on earth is the mole?

nǐzuìdījià dàodǐ shì duōshǎo？wǒ bú xiǎnɡ ɡēn nǐ jiǎnɡjià!
你最低价 到底 是 多少？我 不 想 跟 你 讲价!

Come on, give me your lowest price, I'm not in the mood for haggling.