> We have signals for left turn, right turn, and stop. So why don't we have one for straight ahead?

We do. It's an undocumented feature on most vehicles. You activate it by not touching the signal switch. The car will automatically determine that you are going straight and relay that information to the other drivers.

> Signs on the Interstate say, "Slower Traffic Keep Right." Slower than what?

The speed limit. If you want to drive in the main lanes, you'd better go faster.

> It's the same with the "Do Not Pass" sign. Does that mean that you can't pass the sign?

Passing a sign sounds painful regardless of what it says, so probably not.

> Howard

Nyperold