I am always confuse with the usage of "fish" and "fishes". As a student, we were taught that there is no plural form for the word "fish". Like the word 'furniture', it can be used for both singular and plural form of the word. However, when i become a teacher and reads more English materials, I find that "fishes" is often used as a plural form for 'fish'. When my students ask about this, i just don't know how to explain the different usage of the words. Has the rule change?
*****
NOT A TEACHER *****
(1) If you need a "rule" for your students, you might use this
"rule" from
The Columbia [University] Guide to Standard American
English:
"[Fishes] is either archaic [old and no longer used in modern
English], as in biblical use [it is found in some translations of the
Bible], or chiefly by biologists and others distinguishing various
kinds or species of fish."
(2) In other words, you can assure your students that "fish" in
ordinary everyday English is simply "fish":
I love fish.
Go to the market and buy some fish.
Many nations are fighting over the fish in the ocean.
Doctors advise us to eat more fish.
(3) If your students ever have need to speak about the various kinds
of fish, it
might be better to use the other plural:
I love this book. It describes in detail all the fishes of Antarctica.
(All those sentences are
only mine, not from any book.)
*****
NOT A TEACHER *****