I can say that I've caught a cold and have a headache, understand the doctor's advice — what to do and why — and give advice myself: “Since it's cold, stay home.”
Have to, and why: -어야 돼요 and -(으)니까
Have to, and why: -어야 돼요 and -(으)니까
What for: at the doctor's or the pharmacy, to understand what you have to do and why, and to give your own reason.
“Have to”: the stem + -아야 돼요 / -어야 돼요; the vowel is chosen as in 해요체: 가야, 봐야, 먹어야, 쉬어야, 써야; 하다 gives 해야 돼요. Instead of 돼요 you can say 해요: 가야 해요 means the same.
It's spelled 돼요: 되 + 어요 → 돼요; in the past, 됐어요. 돼요 and 되요 sound the same, but 되요 is a spelling mistake.
“Because”: -니까 after a vowel (가니까, 아프니까) and -으니까 after a consonant (많으니까, 있으니까). ㅂ-irregular verbs: 춥다 → 추우니까; ㄹ-stem verbs drop ㄹ before ㄴ: 멀다 → 머니까.
The reason comes first, the advice second: 눈이 오니까 천천히 가세요. Before a request with -(으)세요, give the reason with -(으)니까.
왜 is “why”; the answer gives a reason. 그래서 is “so, that's why” at the start of a sentence; 그러니까 is “so, therefore”; before a request (-(으)세요) only 그러니까 works: 그러니까 쉬세요, not 그래서 쉬세요.
“I caught a cold” is 감기에 걸렸어요: learn it as a whole.
The doctor may also say “don't smoke”: 피우지 마세요 (담배 — cigarette, 피우다 — to smoke). Learn this phrase as a whole too.
Common mistakes:
• NOT 먹야 돼요 → 먹어야 돼요.
• NOT 가야 이에요 → 가야 돼요 (no 이에요: 돼요 is the verb).
• NOT 되요 → 돼요.
• NOT 먹니까, 춥으니까, 멀으니까 → 먹으니까, 추우니까, 머니까.
“Have to” and “because”
The vowel in “have to” is the same as in 해요체. 으 in “because” comes only after a consonant.
| Dictionary form | Have to | Because |
|---|---|---|
| 가다 | 가야 돼요 | 가니까 |
| 먹다 | 먹어야 돼요 | 먹으니까 |
| 쉬다 | 쉬어야 돼요 | 쉬니까 |
| 하다 | 해야 돼요 | 하니까 |
| 쓰다 | 써야 돼요 | 쓰니까 |
| 춥다 | 추워야 돼요 | 추우니까 |
| 멀다 | 멀어야 돼요 | 머니까 |
Lesson notes
Have to, and why: -어야 돼요 and -(으)니까
What for: at the doctor's or the pharmacy, to understand what you have to do and why, and to give your own reason.
“Have to”: the stem + -아야 돼요 / -어야 돼요; the vowel is chosen as in 해요체: 가야, 봐야, 먹어야, 쉬어야, 써야; 하다 gives 해야 돼요. Instead of 돼요 you can say 해요: 가야 해요 means the same.
It's spelled 돼요: 되 + 어요 → 돼요; in the past, 됐어요. 돼요 and 되요 sound the same, but 되요 is a spelling mistake.
“Because”: -니까 after a vowel (가니까, 아프니까) and -으니까 after a consonant (많으니까, 있으니까). ㅂ-irregular verbs: 춥다 → 추우니까; ㄹ-stem verbs drop ㄹ before ㄴ: 멀다 → 머니까.
The reason comes first, the advice second: 눈이 오니까 천천히 가세요. Before a request with -(으)세요, give the reason with -(으)니까.
왜 is “why”; the answer gives a reason. 그래서 is “so, that's why” at the start of a sentence; 그러니까 is “so, therefore”; before a request (-(으)세요) only 그러니까 works: 그러니까 쉬세요, not 그래서 쉬세요.
“I caught a cold” is 감기에 걸렸어요: learn it as a whole.
The doctor may also say “don't smoke”: 피우지 마세요 (담배 — cigarette, 피우다 — to smoke). Learn this phrase as a whole too.
Common mistakes:
• NOT 먹야 돼요 → 먹어야 돼요.
• NOT 가야 이에요 → 가야 돼요 (no 이에요: 돼요 is the verb).
• NOT 되요 → 돼요.
• NOT 먹니까, 춥으니까, 멀으니까 → 먹으니까, 추우니까, 머니까.