Since you are already talking to your children everyday, why not take the opportunity to expand their vocabulary with "big English words"?
WATCH the psychologist, Haim Ginott, demonstrate this technique in the hilarious video below.
THEN, sit down with a cup of coffee and a pencil to make a few "vocabulary play lists" of big English words--and use them everyday instead of their more common synonyms in the home (or classroom).
SOME SAMPLE PLAYLISTS for you:
When your child is particularly wise: "How astute/discerning/ingenious/ erudite/ prudent/ savvy/sagacious/ shrewd you are."
When she is stubborn: "My! This is obstinate/recalcitrant/willful/ intractable/dogged behavior."
When he is enthusiastic: "You must really like this. I have not seen you so ardent/avid/ebullient/effervescent/exuberant/fervent/vibrant in a long time."
When playdate friends are getting along well: "You are so affable/amiable/amicable/congenial/cordial/convivial/gregarious today."
When a child is talkative: "You are really eloquent/garrulous/loquacious/verbose/voluble today."
For the teen in the Who Cares? phase: "Is there something wrong? You seem a bit aloof/apathetic/indifferent/listless/nonchalant today."