Can someone clarify why 里 is required here? I assume it has to do with the water not being in the glass rather than the glass simply not having water, but this construction and its usage are unfamiliar to me.
Yes the 里 is essentially the "in" from the English sentence.
Lit: "The glass interior doesn't have water".
This is a specific sentence structure which uses 有 in a special way.
Location+有+Thing = There is/are Thing at Place.
杯子里 (inside the glass) is the location. 杯子 by itself isn't really a location.
I'm a little confused with the word order. I thought it would be 杯子没有水里. Can someone please clarify?
The preposition 裡/里 means inside and it relates to the noun directly before it.
杯子裡 = the inside of the cup
沒有水 = has no water
Your word order seems natural following English grammar, it might translate something like "the cup has no the inside of the water."
水里 would mean inside the water instead of inside the glass 杯子里。Another user explained it to me like this: 里 (inside) has to follow the object it relates to, such as 冰箱里 （inside the refrigerator).
Why can't the sentence be reversed, like this?
没有 means "does not have". The reverse order becomes more or less "Does not have water in (this) glass", which does not work grammatically.
Very clean and clear explanation... Is there any grammar support in duolingo.... I have been so far following duolingo however I feel that I need to learn some grammar features before continuing
Inside each lesson, there is a light symbol and a key symbol. The light symbol contains the grammar, which evolves from easy to difficult levels.
What's the difference between 玻璃 and 杯子 ?