「才」

「就」的反面。早了 → 就。晚了 → 才。

他八点就到了。     He arrived as early as 8.     真早
他八点才到。       He didn't arrive until 8.     真晚

三张脸

他才回来。         He just got back.             刚刚
只有这样才行。     Only this way works.          唯一条件
你才傻！           YOU are the dummy!            反击

动手

我昨天才知道。

✅ I only just found out yesterday. / I didn't know until yesterday.

必须努力才能成功。

✅ You have to work hard to succeed. / Only hard work leads to success.

他才不会来呢。

✅ He's not gonna come, trust me. / No way he'll come.

就 vs 才 对照

5 点就到了     arrived (as early) as 5     暗含：早
5 点才到       didn't arrive until 5        暗含：晚

同一个时间，「就」和「才」带的语气完全相反。英文没有这个字，靠 as early as / not until 或语气词补上。

——下一课：「还」。