同屋 in English:

My roommate is prodigal when it comes to spending money on movies; he buys them the day they're released, regardless of price.

My roommate is learning Chinese.

I'm having trouble with my roommate. He eats all my food.

Mark is a good roommate, but he can be too much of a neatness freak.

Moskovitz and Zuckerberg were roommates.

My new roommate is a very intelligent guy

My beer was finished off by my room-mate.

In an oddly brotherly drunken gesture, Cole tried to give his roommate a noogie.

Has my roommate been decided?

I'm Paul, your roommate.

His roommate would blacken her toast until it set off the fire alarm.