Lookup a repeated word

hi excelers,
I simply need help to find a repeated word across two arrays i.e:

A1
Boy
Cat
Dog

B1
Dog

C1
= 1

(if others words are find it should = 2)

the solution should be a simple one, hope its explained clearly for you... thanks for any further help.

When you enter this formula, be sure to hold down CTRL+SHIFT+ENTER instead of only ENTER.

=IFERROR(COUNT(MATCH($A$1:$A$3,$B$1:$B$3,0)),0)

thanks, it works...
but I need it to also work with a block array of words from say A1:C3 etc... via two blocks.