That's an easy one! Mice is the plural of mouse. One mouse, two mice. All the best Steve

Mouse is singular, one mouse. Mice is the plural form of mouse, more than one.

When I was little, I had a pet mouse. (singular) When I was little, I had pet mice. (plural) I fear mice. (In general, no matter what the mouse looks like or it's size). I fear the mouse. (a mouse specifically, other mice wouldn't bother you). Do you have mice?(usually as in a PEST problem) Do you have a mouse? (usually as a PET) Many ways of using it, but singular and plural are the basis of the word. Other animals have a plural that changes like this. Goose->Geese Octopus->Octopi