I think if you have some example, let me show. That is better to explain. haha First thing "참다"' is equivalent for "endure" or "be patient" or "put up with" or "stand" or "bear" and so on.. And that is verb.(present tense. If you want to say past tense, you should say "참았다". "참을 것이다 or 참을거야" like these form are future tense. For example, you could say like these "나는 고통을 참았다" or "나는 화를 참았다" http://alldic.daum.net/word/view.do?wordid=kew000070027&q=%EC%B0%B8%EB%8B%A4 (You can find variety examples in here. ) Second thing "겪다" is equivalent for "experience" or "suffer" and so on. And this form is verb. If you want to say past form, you can say "겪었다". ex. 나는 오늘 이상한 일을 겪었다. ex. 나의 할아버지는 6.25 전쟁을 겪었다. Here is website you could find some examples about this word. http://alldic.daum.net/word/view.do?wordid=kew000003708&q=%EA%B2%AA%EB%8B%A4

겪다 is 'go through'. Also it means experience and it has negative nuance. For example) 기분 나쁜 일을 겪다. 참다 is 'endure', 'bear','have patience'. For example) 배가 고팠지만 참았다. / 눈물이 나지만 참았다.