Synonyms= two words that carry nearly the same meaning 1. "How do you tell the difference between English synonyms? This, truthfully, is not necessary. The synonyms are similar in meaning and have the same uses. However, if you really want to go in-depth, look in a dictionary for any small differences. 2. "How do you know IF a word is a synonym?" This is based on good vocabulary skills. The skills needed to determine the synonym for an English word is based on the extent of your vocabulary. I am sure you can also find some lists of common English synonyms online. You can also use a thesaurus as Gracy mentioned. Source: self (American English)

I think your question is going to ask people "how to tell the difference between synonyms" hmmm.... i think there is many synonyms in English... and my way to tell them is to recite and read more books when you are reading a book you can see the difference in the text before and after , you will discover that there are many synonyms ........ recite it easier ... or another is that you can find the dictionary in the bookstore (surf the net to find some) I recommend you a website which can learn more synonyms "http://thesaurus.com/" which about many synonyms and you will know much more synonyms you dont know it yet.... Briefly... the best way to tell them apart is that you must read and take a note more you will acheive if you really make good efforts :D