"Yes, the boy is calm."
Translation:Oui, le garçon est calme.
Both translate to "the" and words in french can either be masculine (le) or feminine (la). It is something you will learn with repetition on which is which. A big helping point for me was learning that about 80% of Nouns that end with an "e" tend to be feminine. And then we just have to remember the other 20%!
es is used with you (singular) as 'you are' (tu es), and est is used with il and elle (3rd person singular) as 'he/she/it is' (il/elle est). To sum up, 'es' is 'are', and 'est' is 'is'.
If the word starts with a vowel (or a vowel sound e.g l'homme sounds like l'omme) then you put an apostrophe. l'garcon is wrong because garcon doesn't apply.
Can some help help to understand the differences between l' , la, le ? Please