How to test whether a word is in singular form or not in python?

Question

I am trying to get whether a word is in singular form or in plural form by using nltk pos_tag. But the results are not accurate.

So, I need a way to find how can get whether a word is in singular form or in plural form? moreover I need it without using any python package.

Answer 1

For English, every word should somehow have a root lemma where the default plurality is singular.

Assuming that you have only nouns in your list, you can try this:

from nltk.stem import WordNetLemmatizer

wnl = WordNetLemmatizer()

def isplural(word):
    lemma = wnl.lemmatize(word, 'n')
    plural = True if word is not lemma else False
    return plural, lemma

nounls = ['geese', 'mice', 'bars', 'foos', 'foo', 
                'families', 'family', 'dog', 'dogs']

for nn in nounls:
    isp, lemma = isplural(nn)
    print nn, lemma, isp

You will have a problem when word is out of wordnet, then you have to use more sophiscated classifier or finite state machines out of NLTK.