On any given morning a bride may tiptoe into Robert T. Nash's office dressed in a gown of delicate lace, clutching the hand of a groom wearing a tuxedo and stiff-collared shirt.

Right on their heels could come another bride and groom, both sporting blue jeans, rushing into Nash's office to say "I do" before their lunch hour ends.

An impeccable dresser, he performs each wedding ceremony standing in front of the large wooden desk in his private office. The loving couple faces him. On special occasions, such as this Valentine's Day week, he's booked solid.

Since 1971, when he became the chief deputy clerk of the Marriage License Bureau, Nash has married about 6,000 couples. They come to the bureau in the Superior Court Building, 515 Fifth St. NW, dressed in a variety of ways, but generally wearing wide, wide smiles.

"I get them ready to fight," said Nash. "A whole lot of them I see I don't want to marry, but I can't let my feelings get into it. They don't ask any advice and I don't give any."

He limits himself to five ceremonies a day, spending the rest of the day overseeing the operation of the bureau. It takes him two minutes to marry a couple. "I'm not a slow reader," he said, laughing.

There are people he'll never forget, such as the male police officer who had a sex change operation and married a retired fireman, and the 75-year-old man who married the 19-year-old woman.

"He looked like he was in his fifties," he said, shaking his head. "No way would I have guessed the man was 75."

One of his most unforgettable ceremonies, Nash said, "was when I married a girl who was in labor. She was moaning through the whole ceremony. I didn't know what was going on until I looked outside and saw an ambulance waiting on her.

"I was scared to death," he remembered. "Now when a pregnant woman comes in the first thing I ask is, 'How many months pregnant are you?' "

On Tuesday, three days before Valentine's Day, a snowy day that brought some businesses to a halt, Nash continued his duties as usual. Shortly after 1 p.m. he pronounced Lam V. Le, 25, and Patricia Santamarianova, 21, husband and wife. The bride wore a knee-length white dress she bought especially for the occasion and the groom wore a pastel blue suit he pulled from his closet.

The couple met a year ago in an "English as a Second Language" class at the Gordon Center, 35th and T streets NW. She is from France; he is from Vietnam.

They strolled into Nash's office this week accompanied by a group of nine relatives and friends, and they left a few minutes later, headed for a quick meal at the Samurai restaurant in Georgetown before Lam Le had to return to his job as a waiter at the Ramada Renaissance.

"I spoke very little English," Le said of his initial meeting with his new wife. "We spoke to each other by sign language.

"Before I love her, first I got to know her as a friend," he said. "I love her personality. She is nice to everyone."

"We wanted to get married Valentine's Day but there were not any appointments open," said the bride. adding, "We will have a celebration later and my parents are going to come over from France."

As soon as the couple and their wedding party left the bureau office, Nash directed Monica Browne, 22, and George Young III, 29, back to the ceremonial office.

Browne met Young five years ago when she went to the Vital Records Division of the Department of Human Services to get a copy of her birth certificate and he waited on her.

"It was something about her, maybe her walk," Young said, laughing. "Or maybe it was those tight jeans."

But in a more serious mood later, he said, "We are so much alike. We don't smoke or drink. Both of us were in terrible accidents when we were 8 years old . . . . But we both came through it and I think it makes us take life one day at a time."

They left hand in hand, tramping through the snow with their two small children trailing behind them.

"You can tell if it's love," Nash offered, but when asked how, he had a difficult time explaining.

"You can look at the faces," he said. "She, er, she looks at his face as if, as if she could melt. He, er, his face glows . . . . You can tell. You can just tell."