SUBSIDIZED PARKING may disappear, and riding public transit may be the patriotic thing to do, but we haven't noticed any stampede to the bus stops around town-and there's a reason. If you have lived here any length of time and have never ridden a bus, you know what we mean: Learning how to use Metro can be a mid-career crisis, an infinite string of things you think you should know but are too embarrassed to ask.Bus routes, fares and schedules, are known only to certain native Washingtonians who learned them from the griots over the generations.

Forget the poor tourist who tries to crack the system-for that's what Metro seems to do. Even if you think you know the city, how do you know where a bus might take you when all it says is "Ivy City" or "Pinehurst"? Or stand at a stop, as we did on a test run yesterday, and look for some shred of information, map, clue, hint of what goes on there. The sign was plastered over a terribly timely tip that says, "Routes changes as Feb. 19, 1978/Consult new timetable or call 637-2437." There was no timetable for us, of course, nor, judging from sign, for Metro.

The bold thing to do is ask a driver. The hard part is to know in what language, for many do not seem to speak except in a series of grunts as they look down their fare boxes at you. Even "how much?" is considered a stupid inquiry, since there is no short answer and no hint when you board a bus-even though you need exact change for it.

Metro always says improvements are on the way-better graphics, new maps, courteous drivers, telephone numbers that are answered by real people and the like. Time and again, too Metro has conducted surveys on the buses to find out what its riders think of the system. But what about the would-be riders , who aren't asked what it would take to lure them out of their cars? Higher gasoline and parking prices? Maybe. But unless Metro overhauls its information system and establishes an understandable route system, people are going to ride that last mile on their own four wheels.