Ive heard on shows people use 귀엽다 without changing it to 귀여워(요) why is that? Are there times when you retain the dictionary form of a word in speech?

letstteok-korean:

The reason for that is the fact that adjectives (I believe) can be said as its original form when speaking informally to someone. 

So in this case, you would only use 귀엽다 when speaking to someone close to you or younger than you. 

Every word is able to be configured into formal, informal and so on. 

The narrative plain tense (action verb)~ㄴ/는다 (adjective verb)~다 can be use to in informal speech to narrate a present action:

나 간다 = i’m going/leaving

Or as an exclamation:

너무 귀엽다! = it’s so cute!
우아 예쁘다 = wow, she’s pretty.
아 좋다.. = aah, this is good..

narrative present tense

image

~ㄴ/는다 (action verbs)
~다 (descriptive verbs)

자다 (to sleep) → 잔다
굽다 (to bake) → 굽는다
팔다 (to sell) → 판다

1. shows reaction of impression, surprise, excitement (반말)

이거 좋다! = This is good!
여기 강아지 있다! = There is a puppy here!
저기 기차 지나간다. = Over there, there is a train passing by
전화 온다. = The phone is ringing
오늘 날씨 좋다! = The weather is good today!
전화가 안 돼요. 어? 다시 된다! = The phone is not working. Huh? It’s working again!
저기 내 친구들 온다 = There come my friends

2. narrating present action (반말)

나 먼저 간다. = I’m leaving now (before you) “Hey, I am leaving now, as you can see. Tell me now if you want to show some reaction.”
그러면, 다음에는 너 초대 안 한다. = If you do that (If that’s the case), next time, I won’t invite you (as a general rule or habit)
그럼 나는 여기서 기다린다? = Then I will wait here, okay?
한국어를 잘 하고 싶으면, 매일 공부해야 한다. = If you want to speak good Korean, you need to study everyday.

3. neutral (no politeness level) narrative language for series of actions like in diary, documentary, recipes etc. (neutral formality)

경은은 오늘도 아침 8시에 일어난다. 일어나서 제일 먼저 하는 일은 핸드폰을 보는 것이다 – Kyeong-eun gets up at 8 AM as usual. The first thing she does after she gets up is checking her cellphone.
이 학교에서는 500명의 학생들이 한국어를 배운다 – In this school, 500 students learn Korean