It is a excerpt of the listening section of Toefl pre-test.
"Uh, other things that glaciers can do is, uh, as they retreat, instead of depositing some till, uh, scraped up soil, in the area, they might leave a big ice block and it breaks off and as the ice block melts it leaves a dpression which can become a lake."
Please tell me!!
It's Greek to me. XO