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Post date	Users	Rates	Content
Wed, 02/27/2013 - 22:05	Lauren	88	Check this topic
Tue, 10/28/2014 - 11:33	svt.ntu	85	Check this topic
Wed, 06/17/2015 - 00:31	piyo	53	Check this topic
Mon, 02/25/2013 - 04:26	Vanan	100	Check this topic
Mon, 02/25/2013 - 04:07	Vanan	95	Check this topic

Topic title: With points from the lecture, explain the formation of collapse sinkhole.

Topic category: TOEFL speaking