Please note that we have added a consequence for failure. Any contact with the chamber floor will result in an unsatisfactory mark on your official testing record, followed by death.

This is your fault. It didn't have to be like this. I'm not kidding, now! Turn back, or I will kill you! I'm going to kill you, and all the cake is gone! You don't even care, do you? This is your last chance!

You are kidding me. Did you just stuff that Aperture Science thing-we-don't-know-what-it-does into an Aperture Science Emergency Intelligence Incinerator?

Due to mandatory scheduled maintenance, the next test is currently unavailable. It has been replaced with a live-fire course designed for military androids. The Enrichment Center apologizes and wishes you the best of luck.

Momentum, a function of mass and velocity, is conserved between portals. In layman's terms, speedy thing goes in, speedy thing comes out.