It's not the heat, it's the humidity.
Non calor sed umor est qui nobis incommodat.

God, look at the time! My wife will kill me!
Di! Ecce hora! Uxor mea me necabit!

Is that a scroll in your toga, or are you just happy to see me?
Estne volumen in toga, an solum tibi libet me videre?

The designated hitter rule has got to go.
Lex clavatoris designati rescindenda est.

I think some people in togas are plotting against me.
Sentio aliquos togatos contra me conspirare.

If Caesar were alive, you'd be chained to an oar.
Caesar si viveret, ad remum dareris.

How much wood would a woodchuck chuck if a woodchuck could chuck wood?
Quantum materiae materietur marmota monax si marmota monax materiam possit materiari?

Ever noticed how wherever you stand, the smoke goes right into your face?
Animadvertistine, ubicumque stes, fumum recta in faciem ferri?

Honk if you speak Latin.
Sona si Latine loqueris.

If you can read this you're over-educated
Si Hoc Legere Scis Nimium Eruditionis Habes

I think some people in togas are plotting against me.
Sentio aliquos togatos contra me conspirare.

I saw, I conquered, I came
Vidi Vici Veni

Stupid cow
Vacca foeda

Excuse me. I've got to see a man about a dog.
Mihi ignosce. Cum homine de cane debeo congredi.

Royally screwed
Raptus regaliter

If you can read this sign, you can get a good job in the fast-paced, high-paying world of Latin!
Si hoc signum legere potes, operis boni in rebus Latinus alacribus et fructuosis potiri potes!

I hate Astroturf.
Gramen artificiosum odi.

I'm not interested in your dopey religious cult.
Nihil curo de ista tua stulta superstitione.

Don't call me, I'll call you.
Noli me vocare, ego te vocabo.

It doesn't rhyme.
Nullo metro compositum est.

I don't care. If it doesn't rhyme, it isn't a poem.
Non curo. Si metrum non habet, non est poema.

Make my day.
Fac ut gaudeam.

Those green pants go so well with that pink shirt and the plaid jacket!
Braccae illae virides cum subucula rosea et tunica Caledonia-quam elenganter concinnatur!

Do you want to dance? I know the Funky Broadway.
Visne saltare? Viam Latam Fungosam scio.

Say, you sure are drinking a lot.
Re vera, potas bene.

May barbarians invade your personal space!
Utinam barbari spatium proprium tuum invadant!

May conspirators assassinate you in the mall!
Utinam coniurati te in foro interficiant!

May faulty logic undermine your entire philosophy!
Utinam logica falsa tuam philosophiam totam suffodiant!

Couch potato
Radix lecti

What's your sign?
Quo signo nata es?

Oh! More! Go on! Yes! Ooh! Ummm!
O! Plus! Perge! Aio! Hui! Hem!

Honey, I'm home.
Mellita, domi adsum.

I am as dead as the nehru jacket.
Tam exanimis quam tunica nehru fio.

Go with the flow.
Ventis secundis, tene cursum.

Let it all hang out.
Totum dependeat.

Pretty please with a cherry on top!
Te precor dulcissime supplex!

I am the Master of the Universe!
Magister Mundi sum!

Gag me with a spoon!
Fac me cocleario vomere!

I can't hear you. I have a banana in my ear.
Te audire no possum. Musa sapientum fixa est in aure.

Is that a scroll in your toga, or are you just happy to see me?
Estne volumen in toga, an solum tibi libet me videre?

Take my wife, please!
Prehende uxorem meam, sis!

How much wood would a woodchuck chuck if a woodchuck could chuck wood?
Quantum materiae materietur marmota monax si marmota monax materiam possit materiari?

That's nothing--in a previous life I was a Roman Emperor.
Nihil est--in vita priore ego imperator Romanus fui.

Stand aside plebians! I am on imperial business.
Recedite, plebes! Gero rem imperialem!

Eat my shorts.
Vescere bracis meis.

Everyone is doing it.
Sic faciunt omnes.

Get a life.
Fac ut vivas.

Let's all wear mood rings!
Anulos qui animum ostendunt omnes gestemus!

I have a catapult. Give me all the money, or I will fling an enormous rock at your head.
Catapultam habeo. Nisi pecuniam omnem mihi dabis, ad caput tuum saxum immane mittam.