Try to think of some examples of "bad grammar", or examples of "grammar problems" you have witnessed (such as difficulties that students have when learning the grammar of another language, grammar errors that you see Mandarin speakers make in Cantonese, grammar errors that you see Cantonese speakers make in Mandarin, or other stuff like that).
List at least one English grammar rule (along with an example of "bad grammar" that breaks this rule), and at least one Chinese grammar rule (along with an example of "bad grammar" that breaks this rule).
You can work on this alone or with one or more partners (most activities in this subject can be done with partners if you like).