HSKReadyGet the appHSK 3 · Word classes › Conjunctions › Connecting clauses or sentences
HSK 3 Clause and Sentence Conjunctions: 只有, 只要, 不但, 而且, 如果, 可, 可是, and 然后
This lesson explains how to link clauses and sentences using eight core conjunctions listed at Level 3 of the supplied HSK grammar outline: 只有, 只要, 不但, 而且, 如果, 可, 可是, and 然后.
只有输入正确的密码，才能打开这个文件。
Correct: 只有 introduces a strict prerequisite and pairs with 才 before the modal verb 能.
× 只有输入正确的密码，就能打开这个文件。
Incorrect: Do not pair 只有 with 就 to express a mandatory condition. Use 才 in the second clause instead (see corrected example).
Corrected example: 只有输入正确的密码，才能打开这个文件。
Read the full explanation and examples
How Clause Conjunctions Work in HSK 3
In Chinese, conjunctions that link clauses or sentences often work in pairs or rely on adverbs in the second clause to complete the logical bridge. In the supplied HSK outline, Level 3 groups eight essential clause-linking conjunctions together: 只有 (only if), 只要 (as long as), 不但 (not only), 而且 (but also / furthermore), 如果 (if), 可 (but), 可是 (but / however), and 然后 (then / after that).
Conditions and Hypotheticals: 只有, 只要, and 如果
只有 introduces a necessary condition: the result requires that condition. The standard learning pattern is 只有……才……. Necessary does not mean sufficient: 只有努力学习，才可能通过考试 says effort is required, not that effort alone guarantees a pass.
只有输入正确的密码，才能打开这个文件。
Correct: 只有 introduces a strict prerequisite and pairs with 才 before the modal verb 能.
只要 presents a sufficient condition: meeting it is enough for the stated result. It need not be easy, small, or quick to achieve. It pairs naturally with 就 in the result clause, and does not claim that all other routes are impossible.
只要你给我发个信息，我就马上去找你。
Correct: 只要 introduces a sufficient condition and pairs with 就 after the second subject 我.
如果 introduces a general hypothetical condition without the special only-if or sufficient-condition emphasis. 就 is common in the result clause but can also be omitted in statements, questions, or instructions when the relationship remains clear.
如果明天下大雨，比赛就推迟到下周。
Correct: 如果 sets up a general hypothetical condition paired with 就.
Adding Information: 不但 and 而且
不但 and 而且 work together to build a progressive relationship ('not only... but also...'). Moreover, 而且 can also be used on its own at the start of a second clause to add a further point ('furthermore'). When combining two clauses with 不但 and 而且, word order depends on whether the subject changes.
- Same subject or topic: Place the shared subject before 不但. The second clause after 而且 often includes adverbs like 也 (also) or 还 (still/also).
- Different subjects: Place 不但 at the very beginning of the first clause, before the first subject, and place the second subject after 而且.
这家饭馆不但菜很好吃，而且价格也不贵。
Correct: Shared topic 这家饭馆 stands before 不但, while 而且 introduces the second clause.
不但学生喜欢这个节目，而且老师也经常看。
Correct: Two different subjects (学生 and 老师) require 不但 to stand at the very beginning before the first subject.
Contrast and Sequence: 可是, 可, and 然后
To introduce a turn or contrast between two clauses, HSK 3 introduces both 可是 and 可 (listed as 可1 in the syllabus to distinguish the conjunction from other uses of the character). Both mean 'but' or 'however' and appear at the beginning of the second clause. 可是 works smoothly in both spoken and written Chinese, while single-syllable 可 sounds more conversational and direct.
这件毛衣的颜色很好看，可是对我来说太小了。
Correct: 可是 connects two contrasting clauses.
我很想帮你，可我现在真的没时间。
Correct: Single-character 可 (可1) acts as a natural conversational conjunction meaning 'but'.
To link actions that happen one after another in time, use 然后 at the start of the second clause. Speakers frequently place the adverb 先 (first) before the verb in the first clause to make the chronological order even clearer. Note that 然后 is a conjunction for sequential actions or events, not a preposition before a noun phrase.
我们先去超市买点儿水果，然后坐地铁回家。
Correct: 先 in the first clause and 然后 in the second clause mark a clear sequence of actions.
Common Learner Mistake: Mixing 只有 with 就
For the intended prerequisite meaning in the example, use the conventional pairing 只有……才……. The mixed 只有……就…… form does not express that relationship clearly. 就 itself does not always mean an easy or automatic result; the problem here is the chosen conditional construction.
× 只有输入正确的密码，就能打开这个文件。
Incorrect: Do not pair 只有 with 就 to express a mandatory condition. Use 才 in the second clause instead (see corrected example).
Corrected example: 只有输入正确的密码，才能打开这个文件。
Keep the prerequisite meaning by changing 就 to 才. Changing 只有 to 只要 instead gives a sufficient-condition statement, which is a different claim; do not make that substitution without considering the intended logic.
Frequently asked questions
How do I choose between 只有 and 只要?
只有……才…… presents a necessary condition: without it, the result cannot hold. 只要……就…… presents a sufficient condition: with it, the stated result follows. A necessary condition does not by itself guarantee success, and a sufficient condition need not be easy or produce an immediate result.
Why does the syllabus list 可1 alongside 可是?
The number 1 in 可1 simply distinguishes the conjunction 可 ('but/however') from other meanings of the character 可 in the syllabus dictionary. In meaning, 可 and 可是 both express contrast between clauses, with 可 being slightly more informal and conversational.
Can I put a noun directly after 然后 to mean 'after something'?
No. 然后 is a conjunction that links a subsequent clause or verb phrase ('and then...'). To say 'after a noun or event' (such as 'after class'), use 以后 after the noun or phrase instead.
