i don't understand mandarin english. see, cantonese english makes sense. lexical stress--primary, secondary, etc.--all map nicely onto the tone system of cantonese. like, primary stress maps to high tone. but mandarin doesn't seem to do anything of the sort. So the other day, i'm sitting in math class, and the teacher's talking about X E and X R. I'm like, what-the-F is X E? Don't you mean, E(X), the expectation of X? Then suddenly, it hits me: she's saying, X一跟X二, not XE 跟 XR. Further observation suggested that the phenomenon involves tones: when she wanted to say "r" or "l", she would use ér (sounds like 兒) and él, with mandarin second tone. i wonder if this is a common phenomenon, or if only people in math circles do this.