Continuing Korean. Ross King

더워졌어요 got hot 더워질 거예요 will get hot 더워지지만 gets hot, but . . . 더워질까요? Do you suppose it will get hot?

      The auxiliary 지- is usually inseparable from the infinitive; it is tacked right on to the -어 in pronunciation.

37.	요즘 낮에는 더워지고 밤에는 추워져요. Lately, it gets warm in the daytime and gets cool at night.
38.	날이 갑자기 흐려졌어요. It got cloudy suddenly.
39.	여름 방학 동안에 머리가 길어졌어요. My hair got long over the summer vacation.
40.	재즈음악이 좋아졌어요. I’ve come to like jazz music.
41.	과일값이 비싸졌어요. The price of fruit has gotten expensive.
42.	내 우산이 없어졌어요. My umbrella has disappeared.
Finally, note that whereas it is impossible to use adjectives like 더워요 directly in the construction with -기 시작해요, you can first put it in the -어져요 construction and then use it like any other processive expression.
43.	더워지기 시작했어요. It started getting hot.
44.	숙제가 점점 어려워지기 시작해요. The homework is gradually beginning to get (more) difficult.

      18.5. Can/Cannot Do: -(으)ᄅ 수 있-/없-

      You have already seen a few patterns that incorporate the prospective modifier -(으)ᄅ:-(으)ᄅ 까요? -(으)ᄅ 거예요 and -(으)ᄅ게요. The noun 수 means case, circumstance; way, means and 수(가) 있어요 means literally a means exists. Following the prospective modifier this pattern conveys possibility and/or ability.

      Expressions meaning can and can’t are made in Korean by attaching -(으)ᄅ 수 (pronounced -(으) ᄅ 쑤) plus 있어요 or 없어요 to any plain base. The way in which this is done is exactly the same as you learned for attaching the probable future form in section 13.3 and the wanna form in -(으)ᄅ래요 in section 12.7. That is because the first ᄅ of all those endings is the same—the prospective modifier that we look at in its own right later on. So, for example, L-extending bases attach the ending to the unextended base.

살 수 없어요	can’t live (base 사-ᄅ-)
애기가 걸을 수 있어요?	can the baby walk?
쓸 수 없어요	can’t use
볼 수 있어요?	can [we] see?
따뜻할 수도 있어요	(you never know, it) can also be warm
구울 수 없어요	can’t broil (base 구w-)

      Expressions with 수(가) 없어요 correspond to one of the meanings of negative forms with 못: 갈 수 없어요 = 못 가요 or 가지 못해요 can’t go. Here are some more examples of this construction.

45.	사장님을 잠깐 뵐 수 있을까요? Do you suppose I could see the company president for a moment?
46.	오늘 밤에 우리 집에 오실 수 있어요? Can you come to our house this evening?
47.	시간이 없어서，준비를 다 끝낼 수 없었어요. I couldn’t finish the preparations—I didn’t have time.
48.	오늘은 비가 와서，이발하러 갈 수 없었어요. It was raining today, so I couldn’t go for a haircut.
49.	오늘은 거리가 조용하지만，그 길은 복잡할 수도 있어요. Today the street’s quiet, but this road gets [can be] crowded, too.

      18.6. Expressing and with -(으)며

      This two-shape ending can attach to any type of base and means simply and (sometimes also while, i.e., and [simultaneously/at the same time]). Thus, -(으)며 has the same function as one of the usages of the one-shape ending -고. But there are two differences to keep in mind:

A.	-(으)며 is a literary, bookish form, rarely used in spoken language, whereas -고 is widely used in colloquial Korean.
B.	-(으)며 does not have the having done . . . ; does, and then . . . meaning of -고. Its one and only meaning is and.

      Note that L-extending bases keep their ᄅ before -며: 사-ᄅ - → 살며 live, and . . . Here are some examples.