Somewhere between "your grandmother's Cantonese" and "an actual language lesson" sits a category of slang that's been quietly code-switched into English sentences by younger and diaspora speakers for years — and it's having a moment. Here's a working glossary, no lesson plan attached.
The essentials
Add oil (加油) — encouragement, effort, "you've got this." Common enough that it's now genuinely in the Oxford English Dictionary, which is either the most or least surprising thing a piece of slang has ever achieved.
Hea — lazily relaxing, doing the bare minimum with total commitment. A lifestyle, not just a word.
Bo chap — a don't-care attitude, deployed with more range than the English equivalent ever manages.
Yau mo — disbelief, roughly "no way" or "are you serious," best delivered with maximum incredulity.
Mou lei tau — an entire comedic tradition of deadpan absurdist nonsense, worth its own explainer (we wrote one — go read it after this).
Keng — exaggerated storytelling, the friend who turns a five-minute errand into a twenty-minute saga.
GG — game over, borrowed straight from gaming culture and now applied to literally anything that's ended badly.
None of these were built for a classroom. That's exactly why they've survived.
A caution, because it matters
The entire appeal of this kind of slang is specificity — real words, correctly used, not decorative characters slapped on for effect. If you're going to use any of this, use it right, or ask someone who actually speaks the language before you do. That rule applies to us too.
For the philosophy of leaving a joke unexplained, see The Diaspora Kid's Guide to Never Explaining the Joke.