I’m trying to study for my Programming course and I need some help to understand this question.

To verify that a string of characters belongs to a language defined by a grammar, we must create a parse tree that shows that the string can be generated by the grammar.

Consider the following grammar:

<list> -> <item> , <list> | <item> 
<item> -> <left> <item> <right> | <left> <right>
<left> -> A| B | C
<right> -> x | y | z

Choose a string that is in this language and create a parse tree that demonstrates that your claim is true. Identify another string that contains some of these terminals symbols but is not in the language.