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how to recognize the feminine and masculine in French?

A feminine noun is preceded by 'la' and a masculine noun is preceded by 'le' in French.

The majority of feminine nouns end in 'e'. Although there are exceptions.

The ending sound of the word will help you to recongnise them, but be aware that there are a lot of exeptions.No rule is 100% foolproof in French.

Some website uses a lot of categories to sort words (like this website http://french.about.com/od/grammar/a/genderpatterns.htm ) but I think this is too much to be learnable ! It's better to sort words in just about 10 common endings (like words finishing with the sound "o" - regardless of the spelling - are usually masculine) and then just learn as you go.

There is enough material with this subject to fill near an hour !