Question

We have been given a list of words and have to write the plural of them. I have found the answer to each of the words but now have to write rule for each. I know that words ending in ch, x, s or s-like sounds will all end in es. I am having trouble find a rule for words like buffalo, disco, volcano etc (some end in oes or os), I don't know how to explain the rule for this one, I have the same for words like chief, loaf, wife (some end in fs or ves). I cannot find a rule for this one either. Please can someone help. Many thanks.

Answer 1

For words ending in "o" you need to look at the letter in front of it. If the letter before the "o" is a vowel, then add -s. If the letter before the "o" is a consonant, then add -es.

radios
buffaloes
volcanoes

There is no hard-and-fast rule for the words that end in "f" -- you just have to memorize these!!

Answer 2

http://grammar.ccc.commnet.edu/grammar/plurals.htm