Each lending position essentially consists of a supplied and a borrowed part. The ratio of the 2 determine the health of your position. Take the following example:
Supplied
Asset: 1 EGLD
Price: 15$
Loan to Value: 75% (you can borrow up to 75%*15$=11.25$)
Liquidation Threshold: 80% (you get liquidated when your borrowed reaches 80%*15$=12$)