是不是… — Question a whole proposition: set 是 (so) and 不是 (not so) side by side before the verb phrase, asking the listener to confirm the guess.

grammar → 是不是…

TSUMUGU · TBCL 3 (est.) · 語法

是不是… grammar point · tier 2 · confirmation question 是不是+VP (is it the case that …?)

Question a whole proposition: set 是 (so) and 不是 (not so) side by side before the verb phrase, asking the listener to confirm the guess.

Hook inherited from 嗎.

Question a whole proposition

框 · Frame

[subj] 是不是 [VP]？ (是不是 also floats to the front or the tail)

觸 · Trigger

You have a guess about the whole situation and want the listener to confirm or deny it.

序 · The move

1Hold the full proposition you suspect as one verb phrase (生病了, 去, 想走).Is it a whole claim you want confirmed, not a single verb you would split?

2Place 是不是 in front of that verb phrase, leaving the verb whole.Did the main verb stay intact (生病了), not get doubled (生不生病)?

3Read it back as a yes-or-no the listener can answer with 是 or 不是.Does it probe a guess you already lean toward, rather than ask from blank?

例 · Examples

1你臉色complexion不太好not very good，是不是is it the case that生病fall ill了change of state？

You don't look well — are you sick?

界 · Boundary

正反問句

Plain A-not-A doubles the main verb (你去不去？). 是不是+VP leaves the verb whole and fronts the fixed 是不是 over the whole proposition (你是不是去？).

嗎

嗎 asks a neutral yes-no from blank (你生病了嗎？). 是不是+VP carries a guess the speaker already leans toward and asks the listener to confirm.

繫動詞

Here 是 is not the copula linking two nouns (他是學生). It is half of the fixed question unit 是不是, riding in front of an action.

你是不是去不去？ → 你是不是去？ (是不是 already carries the asking; do not also double the verb)

你生不生病了？ → 你是不是生病了？ (a verb + result 生病了 takes fronted 是不是, not a split verb)

你去是不是？ → 你是不是去？／你去，是不是？ (mid-clause it sits before the VP; only a comma lets it tag the tail)

English confirmation tags vary with the verb (you're sick, aren't you? / you went, didn't you?). Chinese fixes one form, 是不是, regardless of the verb it questions.