Any or some?

Kimie and Kazue have asked me about any and some.

We use any in negative sentences, for example:

"There aren't any cockroaches in my house."
"There isn't any coffee in my office."

We use any in questions, for example:

"Are there any chopsticks on the table?"
"Is there any beer in your fridge?"

We use some for affirmative sentences, for example:

"There are some roses in my garden."
"There is some cake in the cupboard."