Outside of class I asked my mainland Chinese roommate for assistance, but my pitifully incomplete description of the sounds didn't give him much to go on, and, not surprisingly, he couldn't figure it out.
Eventually I learned that the teacher had been saying 譬如說 (pì rú shūo; "For example"), which explained why she couldn't tell what I was referring to from her lecturing -- it was only a helper phrase, never a major, or even minor, lesson point. By that stage of my Chinese studies, I think I had actually already heard elsewhere some different ways of saying "For example", but couldn't make the connection.
Here are other common ways of saying "For example" (capital F because this phrase is always used at the beginning of a sentence, never at the end). I've personally heard native Chinese speakers use all of them:
- 比方說 (bǐ fāng shuō)
- 比如說 (bǐ rú shuō)
- 好比說 (hǎo bǐ shuō)
- 舉例來說 (jǔ lì lái shuō)
- 例如說 (lì rú shuō)