A black cat sat on a mat and ate a fat rat

1.

2.

Did it eat a rat?
Yes, it did

3.

Did it eat a bird or a rat?
It ate a rat

4.

Where was the cat sitting?
It was on the mat

5.

Who did it eat?
It ate a rat

6.

The rat was fat, was not it? Yes, it was

7.

Tell me what color is this cat?
It is black