副词：一直

一直 (yìzhí) is an adverb with two primary uses:

**Use 1 — Temporal (continuously, without stopping):** Place 一直 before the verb or the 在+VP construction. It indicates that an action has been going on without interruption. Often paired with 都 to add emphasis: 他一直都在学习 (He has been studying the whole time). A time span can be added with 从…一直到… (from… all the way to…): 她从早上一直到晚上都在工作 (She worked from morning all the way to evening).

**Use 2 — Directional (go straight ahead / keep going):** Place 一直 before a movement verb or direction word to indicate going straight without turning. Examples: 一直走 (keep walking / go straight), 一直往前 (keep going forward). This is very common when giving directions in Chinese.

**一直 vs 总是:** • 一直 = uninterrupted continuity: 他一直在哭 (He's been crying non-stop). • 总是 = habitual behavior: 他总是哭 (He always cries / he cries every time). The key difference: 一直 stresses no break; 总是 stresses regularity/habit.

**一直 vs 始终 (advanced):** • 始终 has essentially the same meaning as 一直 in its temporal sense but is more formal and found in written Chinese. HSK2 learners should focus on 一直.

**When not to use 一直:** • Do not use 一直 to mean 'again' or 'one more time.' For that, use 再. • Do not use 一直 for habitual actions that happen every time. Use 总是 instead. • Do not use 一直 for actions that are completed and not ongoing.