When do we need $v1 in MIPS?

Question

We all know that usually a program will just return one value, but I have noticed that we have two value returning registers $v0 and $v1 in MIPS. T

Answer 1

I can think of plenty of examples, but it's probably just up to your discretion. The best example is probably a function that returns a value in $v0 and may set an error code in $v1.