1. I have two dogs.

One is black, and the other is black and white.

2. I have two dogs.
One is black, and the second is black and white.

(Which expression is correct? Can we use 'the second' instead of 'the other' here?)

2 answers

Yes. Both sentences are correct. But the first sentence is probably the best.
2.I have two dogs.One is black, and the second is black and white.