This lesson is a review and summary of the various types of present tense structures in the Korean language. 

1. Basic Present Tense with "-아/어/여" (Level 1 Lesson 16)
Verb stem + -아/어/여 + -요

Ex)
사다 = to buy
→ 사 + -아요 = 사요 = I buy it. / She buys it. / They buy it. / Buy it.

주다 = to give
→ 주 + -어요 = 줘요 = I give it (to someone). / They give it (to someone). / Give it to me.

저는 매일 운동해요.
= I exercise every day.

저는 한국어를 혼자서 공부해요.
= I study Korean by myself.

2. -시 + -어요 (Level 5 Lesson 2)
The suffix -시 is used to make the sentence honorific when you are talking to or about someone you want to show respect for.

Verb stem + -시 + -어요 → -세요

Ex)
가다 = to go
→ 가 + -시 + -어요 = 가셔요 = 가세요 = He goes. / She goes. / Please go.

모르다 = to not know
→ 모르 + -시 + -어요 = 모르셔요 = 모르세요 = He doesn’t know. / She doesn’t know.

3. -고 있다 (Level 2 Lesson 10)
-고 있다 is used after verb stems to form present progressive sentences. Then again 있다 is conjugated to match the context or the intended tense of the sentence.

Ex)
공부하다 = to study
→ 공부하 + -고 있다 = 공부하고 있어요 = I am studying. / They are studying.

지금 뭐 하고 있어요?
= What are you doing now?

서점에 가고 있어요.
= I am going to the library.

4. -고 싶다 (Level 1 Lesson 13)
-고 싶다 is used to express “I want to”.

Ex)
보다 = to see
→ 보 + 고 싶다 = 보고 싶어요 = I want to see. / I miss you.

뭐 하고 싶어요?
= What do you want to do?

밖에 나가고 싶어요.
= I want to go outside.

5. -(으)ㄹ 수 있다 (Level 2 Lesson 17)
-(으)ㄹ 수 있다 is used to express “can” or “be able to”.

Ex)
찾다 = to look for, to find
→ 찾 + -(으)ㄹ 수 있다 = 찾을 수 있어요 = I can look for it. / I can find it.

여기 주차할 수 있어요?
= Can I park here?

이거 읽을 수 있어요?
= Can you read this?

6. -아/어/여야 되다 (Level 2 Lesson 20)
You can use the -아/어/여야 되다 ending to express “have to”, “should” or “must”.

Ex)
가다 = to go
→ 가 + -아야 되다 = 가야 되다 = 가야 돼요 = I have to go.

이거 먼저 해야 돼요.
= I need to do this first.

조심해야 돼요.
= You have to be careful.

7. -지 않다, 안 (Level 1 Lesson 21)
You can form negative sentences by adding -지 않다 after the verb stem or 안 before the verb.

Ex)
이상하다 = to be strange
→ 이상하 + -지 않다 = 이상하지 않아요 = It’s not strange.
→ 안 + 이상하다 = 안 이상해요 = It’s not strange.

이거 안 비싸요.
= This is not expensive.

그거 별로 안 좋아요.
= It’s not that good.

8. -지 마세요 (Level 2 Lesson 30)
-지 마세요 is used after verb stems to tell someone not to do something.

Ex)
먹다 = to eat
→ 먹 + -지 마세요 = 먹지 마세요 = Don’t eat it.

걱정하지 마세요.
= Don’t worry.

늦지 마세요.
= Don’t be late.

9. -아/어/여요 (Let’s) (Level 3 Lesson 16)
-아/어/여요 looks the same as the plain present tense, but it can be used to form “Let’s” sentences as well.

Ex)
하다 = to do
→ 하 + -여요 = 해요 = Let’s do it.

같이 해요.
= Let’s do it.

지금 가요.
= Let’s go now.

10. -(으)ㄴ 것 같다 (Level 4 Lesson 27)
같다 originally means “to be the same” or “to seem like” but when expressing your opinion about something, you can use -(으)ㄴ 것 같다 to say “I think …”.

Ex)
좋다 = to be good
→ 좋 + -은 것 같다 = 좋은 것 같아요 = I think it’s good.

이상한 것 같아요.
= I think it’s strange.

그 사람 착한 것 같아요.
= I think he’s a nice person.

11. -(으)ㄹ 수도 있다 (Level 3 Lesson 22)
When you want to say that something “might” or “could” happen, you can use the structure -(으)ㄹ 수도 있다.

Ex)
늦다 = to be late
→ 늦 + -(으)ㄹ 수도 있다 = 늦을 수도 있어요 = I might be late. / They might be late.

석진 씨가 알 수도 있어요.
= Seokjin might know.

오늘 집에 있을 수도 있어요.
= I might stay at home today.