You wouldn't buy this bond at par because at par, meaning at $100- because then you wouldn't get any interest on it.

你不是以平价买入,平价买入,意思是以100面值买,否则就没有利息收益了

耶鲁公开课 - 金融市场课程节选

Lots and lots of loans, the securities that people bought at par that were worth about somewhere between zero and $.15 or $.20 and now trade there.

市场上充斥着越来越多的贷款，人们按照面值购买的债券,真正的价值只有大概,0到0。15或者0。20美元0,而它们就这样进行交易。

耶鲁公开课 - 金融市场课程节选

But if they default, you can buy them at $90 and if they can't file their financial statements, you're entitled to par.

但是如果他们违约了，你可以在90美元买进0,但是如果他们没有发布他们的财务报表，你有权以票面价值购进。

耶鲁公开课 - 金融市场课程节选