Last month, Dr. Gridlock asked readers to identify the bad driving habits that most annoy them.

Here are some responses:

Dear Dr. Gridlock:

Here is mine: drivers who speed up or slow down to prevent others from entering the lane in which they are driving.

Darrel Salisbury

Lorton

Dear Dr. Gridlock:

My pet peeve is drivers who run red lights on the pretext of making a right turn on red. Violation is so flagrant that I now find myself slowing down for green lights.

Alan Fila

Falls Church

Dear Dr. Gridlock:

The worst are the dangerous nuts who weave through traffic that is already moving at 70 mph or faster.

They can't seem to stand it if they can see a car in front of them even if the traffic is so heavy they really don't get ahead. [It is] really scary when it is a huge trailer-truck.

School-zone speeders: This is the worst area in the 11 states across the country I have lived in for that stupidity.

Bill Hill

Lake Ridge

Dear Dr. Gridlock:

Drivers should walk around their cars to test whether lights are working properly.

J. Michael Daniel

Annandale

Dear Dr. Gridlock:

Turning right from a center lane and "blocking the box."

Pat Goodwin

Lexington Park

Dear Dr. Gridlock:

* Drivers who block the pedestrian crosswalk at red lights: This causes a very dangerous condition for pedestrians who either have to walk behind or in front of the vehicle.

Going behind risks being backed into if this already careless driver decides to back up without due diligence. Going in front (even if possible) creates a hazard from traffic with the green light.

* People backing or pulling out of parking spots without looking in both directions.

* People pulling out of side streets not looking in both directions.

Ron Berger

Norbeck

Dear Dr. Gridlock:

While I have numerous pet peeves about the driving habits of people anywhere in the United States (like, try driving in Boston), I think the two that upset me the most are the ones that endanger the lives of children and animals.

For example, those parents who don't strap their children into car seats, or people who ride around with their dogs in the backs of trucks.

(And just because you have it in a crate in the back doesn't make it any better if you're stuck in traffic and your dog is panting under the hot sun.)

You hear me, the guy in your nice, air-conditioned truck while your two dogs are panting with no shade in the back of your truck on Interstate 95 north out of Richmond?

But the one that takes the cake is the family traveling north on the Beltway with all its beach stuff piled on top of the car and, sitting precariously on the top, fastened by a single bungee cord: a pet carrier that had a big, orange cat inside.

Lee Martinez

Falls Church

Dear Dr. Gridlock:

This happened to me twice in two days one recent week:

While already in the process of backing out of a parking space, I had to stop as another vehicle zipped behind me, then came to a dead stop behind my bumper while waiting for someone to back out of another space a few feet closer to the store, forcing me to wait, halfway out of my space, to complete my exit.

Heaven forbid yielding to my exit and risking loss of another space two car widths closer!

The second time that happened, a woman in a gigantic van blocked me, just inches from my bumper, for more than a minute, ignoring my tap and then full blast of the horn -- my only way to suggest that she was inconveniencing someone with things to do and places to go.

Jan Fisher

Arlington

Transportation researcher Diane Mattingly contributed to this column.

You can write to Dr. Gridlock at 1150 15th St. NW, Washington, D.C. 20071. He prefers e-mails to drgridlock@washpost.com or faxes to 703-352-3908.

Include your full name, town, county and day and evening telephone numbers.

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