Dr. Gridlock,

What are the names of the driving schools which offer defensive driving and other extensive driving programs you have mentioned in your column?

Readers have recommended Car Guys and BSR Inc., which offer more advanced classes for students (young and old) who already have a license, and Lampshire, which has classes for those who have at least a learner's permit.

• Car Guys offers courses in Rockville and at Stonewall Jackson High School in Manassas. Cost is $250 for a one-day course. Call 1-800-800-GUYS (4897) or visit the Web site, www.carguys.com

• BSR Inc. is in Charles Town, W.V. Cost is $295 for a one-day course. Call 304-725-6512 or visit its Web site at www.bsr-inc.com/bsr/.

• Lampshire Driving School is in Woodbridge. Call 703-221-0222 or 703-360-8567 or visit its Web site at www.thedrivingschool.com.

• AAA Driving Schools offers a course in Rockville. For more information, call 1-877-457-0711.

Dr. Gridlock,

What does HOV mean, and what are the HOV hours in the metropolitan area?

HOV means high-occupancy vehicle, something of a misnomer because most HOV restrictions require only two people per vehicle.

Motorists who meet HOV minimums can use express lanes reserved for them during rush hours. The hours vary. Here goes:

• Virginia I-395/95 has a 30-mile, two-lane, barrier-divided facility in the highway median between Prince William County and Washington. The lanes are reversed for rush-hour travel and are restricted at those times to vehicles with a minimum of three people (HOV-3). At times other than rush hours, the lanes are open to all traffic in certain directions.(Because this I-395/95 area is affected by the Springfield Interchange project, you can call 1-877-95-95-222 for the most up-to-date information about lane closings.)

  Weekdays:

  6 to 9 a.m., northbound for HOV-3 vehicles only.

  9 to 11 a.m., northbound for all traffic. 11 a.m. to 1 p.m., closed while crews reverse lanes.

  1 to 3:30 p.m., southbound for all traffic. 3:30 to 6 p.m., southbound for HOV-3 vehicles only.

  6 to 9 p.m., southbound for all traffic.

  9 to 11 p.m., closed while crews reverse lanes.

  11 p.m. to 6 a.m., northbound for all traffic.

  Weekends:

  6 p.m. Friday to 2 p.m. Saturday, southbound for all traffic.

  2 to 4 p.m. Saturday, closed while crews reverse lanes.

  4 p.m. Saturday to 6 a.m. Monday, northbound for all traffic.

• I-270 express lanes in Montgomery County: This involves one lane in each direction, marked with a diamond painted on the pavement and reserved for HOV-2 traffic during weekday rush hours.

  6:30 to 9 a.m., HOV-2 only in the southbound HOV (diamond) lane.

  3 to 6:30 p.m., HOV-2 only in the northbound HOV lane.

  Weekends and all other times, the HOV lanes are open to everyone.

• Virginia I-66

  Inside the Beltway, weekdays:

  6:30 to 9 a.m., all eastbound lanes are reserved for HOV-2.

  4 to 6:30 p.m., all westbound lanes are reserved for HOV-2.

  Outside the Beltway, weekdays:

  5:30 to 9:30 a.m., the inside, diamond lane eastbound is reserved for HOV-2.

  3 to 7 p.m., the inside diamond lane westbound is reserved for HOV-2.

  Weekends and all other times, there are no HOV restrictions.

• Dulles Toll Road

  Dulles Toll Road from Route 28 to the Beltway:

  6:30 to 9 a.m., one diamond lane reserved for eastbound HOV-2 travel.

  4 to 6:30 p.m., one diamond lane reserved for westbound HOV-2 travel.

• Maryland Route 50

  The Maryland State Highway Administration is planning to construct an HOV-2 lane in each direction on Route 50 starting next spring. The lanes will be constructed on the existing inside shoulders, and a new, four-foot inside shoulder will be built as a replacement. The HOV lanes would be built for eight miles between the Beltway and the Route 301 interchange. Work should be finished by summer 2002. There are no plans to construct HOV lanes on Route 50 in Anne Arundel County.

• HOV exemptions: motorcycles; vehicles going to or from Dulles International Airport on business; vehicles with clean fuel license plates; emergency vehicles; law enforcement vehicles; and public utility vehicles responding to emergency calls.

Dr. Gridlock,

Do you have any advice for someone looking to take classes to learn motorcycle safety?

The Motorcycle Safety Foundation offers beginner classes in Maryland and Virginia. The courses are for 20 hours, usually during a long weekend. Motorcycles and all gear are provided. The cost is $50 to $100. Motorcycle operators in Virginia, Maryland and the District must pass a skills test and a written test to be licensed.

In Virginia, register through the Northern Virginia Community College campuses in Alexandria, 703-845-6240, or Loudoun County, 703-450-2551.

For the Maryland courses, call 1-800-638-1722 within Maryland. From outside Maryland, call 410-508-2436.

Dr. Gridlock,

I missed one of your license plate riddle answers. Can you share them?

• 4x4x8 - Honda Accord

• BAABAA - black Jeep

• ML8ML8 - white Volkswagen Rabbit

• WISPYCLD - Chrysler Cirrus

• JULIET - Alfa Romeo

• ISLEOF - Ford/Mercury Capri

• BEYOND - blue Plymouth Horizon

• 1 DIV 0 - Infiniti

• R PFERD - our Ford Mustang

• PENNY LN - blue Suburban

• IXXI - Porsche 911

• STORIES - Saab

• EDUCA8EM - Mazda Protege

• HARK – Triumph Herald

• GSNHT - Isuzu

• IH8RAID - Volkswagen bug

• CASHFLW - Volkswagen GTI

• ROYGBIV - Chevrolet Spectrum (or Prism or Lumina)

• LEAVIN - Volkswagen Jetta

• HG FUR - Mercury Sable

• TLMCHUS - Honda Odyssey (Telemachus was the son of Odysseus in "The Odyssey")

• NOSEEME - Dodge Stealth

• FLT TAX - Nissan Quest (Forbes's Flat Tax Campaign)

• SMOONN - Mitsibushi Eclipse (Moon blocks sun)

• 3TT3V - Chevrolet Corvette (Read in mirror)

• TROILUS - Toyota Cressida (from the Shakespeare play "Troilus and Cressida")

• AG GATO - Silver Mercury Cougar (AG is the symbol for silver; gato is Spanish for cat)

• NOS4SUR - Dodge Shadow (from The Shadow radio show: "Only The Shadow knows for sure")

• I XPLODE - Ford Pinto

• NCC 1631 - Dodge Intrepid (Star Trek Vulcan scientists' ship's registry number is NCC 1631)

• NBE YND - Infiniti (From the movie "Toy Story," Buzz Lightyear says, "To infinity and beyond!")

• 262 MI - Checker Marathon

• 3x10QBD - Mitsubishi 3000GT (3 x 10 cubed is 3000)

• GCANTOR - Infiniti (Mathematician Gregor Cantor showed how to use infinite sets in mathematical problems)

• PICTRMN - Ford Focus

• OF GLORY - Chevrolet Blazer

• AND ROLL - Chevrolet Camaro IROC

• FNDMLOVE - Toyota Avalon (song "I found My Love in Avalon")

• WALABY - Subaru Outback

• WADA ZU - GMC Safari

• INRTGAS - Dodge or Plymouth Neon

• CAML - Answer in March