Have you guys heard of “없어요”? “없어요” comes from the verb “없다” as above. “없어요” is more convenient to use since it’s an independent verb. Most people find it convenient to use 없어요 than “있지 않아요” or “안 있어요” (which is also used to say ‘do not’). So in short, when someone asks “Do you have time?” [시간 있어요?] & your reply would be “I don’t have time.”, you would say, “시간 없어요.”
시간 (shi-gan) = time
있어요 (i-sseo-yo) = have/exists [comes from the verb 있다]
없어요 (eop-sseo-yo) = don’t have/don’t exists [comes from the verb 없다]
Note: Please remember that “보다” is to see. You must conjugate the verb if you want it to be “I see”, it would be “보아요” but Koreans use “봐요” because if you say “보아요” quickly, it would sound more like “봐요”.
보아요 = bo-ah-yo
봐요 = bwah-yo