Korean Infinitives (Vowel-base Verbs)

In today’s lesson, we will continue learning the common verbs in the infinitive form. Previously we learned the Consonant-base verbs, and this week, we will learn the second major type of Korean verbs which involves bases that end with a vowel. Vowel-base verbs are unfortunately somewhat more complex.  

As mentioned previously, there are some rules to follow in deriving the infinitive form and this starts by identifying the base form of the verb.  

Here are 7 important rules to know for vowel ending base verbs. 

1.  If the base ends with the vowel ㅏ, ㅓ or ㅐ, the infinitive is the same shape as the base.   

BASE		INFINITIVE
가-	go	가	goes
서-	stand	서	stands
매-	tie	매	ties
비싸-	be expensive	비싸	is expensive
만나-	meet	만나	meets
보내-	send	보내	sends

2.  For verbs with base form ending in 이, the infinitive ending -어 is added, but 이어 is abbreviated to 여.  In other words, ㅣ + ㅓ = ㅕ. 

For example, the base form of the verb 가르치 teach, the infinitive ending -어 is added to become 가르치어, but is abbreviated to 가르쳐 teaches 

가르치-	teach	가르치어	teaches	>>>	가르쳐
마시-	drink	마시어	drinks	>>>	마셔
치-	hit	치어	hits	>>>	쳐

3.  A similar group consists of bases that end in 우; the infinitive ending -어 is added, and then the sequence 우어 abbreviates to 워.  In other words, ㅜ + ㅓ = ㅝ 

For example, the base form of the verb 주 give, the infinitive ending -어 is added to become 주어, but is abbreviated to 줘 gives. 

주-	give	주어	gives	>>>	줘
배우-	learn	배우어	learns	>>>	배워

4.  Applying the same principle, vowel bases that end in 오 add the infinitive ending as -아 and then 오아 is shortened to 와.  In other words, ㅗ + ㅏ= ㅘ. 

For example, the base form of the verb 오 come, the infinitive ending  

-아 is added to become 오아, but is abbreviated to 와 comes. 

오-	come	오아	comes	>>>	와
보-	see	보아	sees	>>>	봐

FYI, 

note that Korean pronunciation frequently drops w after consonants, especially labial sounds like ㅂ, so you will hear 봐 pronounced as 바.   

내일 봐 [내일 바] 

See you tomorrow. 

5.  There is a slight difference in determining the infinitive form for most vowel bases that end in 으.  The 으 is dropped before adding the infinitive ending -어.  So, the verb base 쓰 write becomes 써 writes in infinitive form.   

However, if the preceding syllable has 오 or 아 vowel, then add the infinitive ending -아 instead of -어.  For example, the verb base 바쁘 be busy becomes 바빠 is busy because the preceding syllable 바 has 아 vowel, thus adding the infinitive ending -아.   

쓰-	write	써	writes
바쁘-	be busy	바빠	is busy

6. Most vowel bases that end in 르 not only drop the 으 but double the ㄹ before adding the appropriate infinitive ending (normally -어, but -아 when the vowel of the preceding syllable is 오 or 아). 

Let’s look an example. The verb base 빠르 be fast becomes 빨라 is fast.  Notice how ㄹ is added to the preceding syllable, and infinitive ending -아 has replaced the base ending vowel 으.    

빠르-	be fast	빨라	is fast
부르-	sing (a song)	불러	sings (a song)
모르-	not know	몰라	doesn’t know

7.  Finally, the 하다 verb is one of the most commonly used verbs.   

This important verb 하~ do has an irregular infinitive: 해.  The literary form of the infinitive, which you may sometimes see, is: 하여 does. 

해요 (Polite Style) 해 << 하여 (infinitive) 하다 (dictionary form)