Unpacking 봤어요
When you see a contracted past form such as 봤어요 , first restore the combination that produced it.
In this regular form, the stem 보- combined with -았어요 to form 보았어요 , which commonly contracts to 봤어요 . The ㅘ in 봤어요 reflects the combination of ㅗ and ㅏ .
Reverse the contraction first: 봤어요 → 보았어요 .
Finding the Dictionary Form
Once we expand 봤어요 into 보았어요 , finding the original word is a simple step-by-step process.
First, remove the past tense ending -았어요 . This leaves you with the stem 보- .
Finally, attach the basic dictionary ending -다 .
The original word is 보다 .
Reverse-Analyzing 왔어요
A related analysis applies to the regular ㅗ-final stem 오- .
왔어요 results from 오- combining with -았어요 and contracting. For reverse analysis, recover the stem-ending relationship directly: 왔어요 → 오- + -았어요 → 오다 .
Do not treat 오았어요 as an ordinary form to use in a sentence. This lesson applies the pattern only to the regular ㅗ-final examples introduced here.
Do Not Build the Past from 봐요
A common mistake is treating the completed 해요-style form 봐요 as an intermediate step in making 봤어요 .
Do not remove 요 from 봐요 and attach another fragment. Return to the dictionary form 보다 , identify the stem 보- , and combine it with -았어요 : 보- + -았어요 → 보았어요 → 봤어요 .
For reverse analysis, follow the same relationship in the opposite direction: 봤어요 → 보았어요 → 보- → 보다 .