Actually it conjugates as "verb stem + ㄴ것 같다" or "noun + 같다" meaning "to seem/look (like)" or "I think/guess/suppose that...".
(ㄴ) 것 같다(dictionary form, narrative form) / 같았다(past tense)
(ㄴ) 것 같아(informal, intimate)
(ㄴ) 것 같아요(informal, polite) / 같았어요(past tense)
(ㄴ) 것 같습니다(formal, polite) / 같았습니다(past tense)
(ㄴ) 것 같이(adverb)
(ㄴ) 것 같은(before noun)
(ㄴ) 것 같았던(used to)
\^o^/