BLACKSBURG, Va. (AP) - Virginia Tech twins Andrea and Michelle Falletti will never forget the day a fellow student gunned down 32 people on campus, but as they prepared to graduate Friday, they said the tragedy wouldn't represent their college experience.

"Looking back on everything these past four years, this is just a little part of it," said Andrea Falletti, 21. "This isn't going to define our graduation or my memory."

As she and her sister walk onto the football field in Lane Stadium with about 5,000 other graduates for Friday night's commencement, she will remember spring breaks, camping trips and partying with friends.

Their parents and grandparents will be in the audience, and it will, at least in some ways, be the graduation they've long envisioned.

"Obviously, what has happened has affected everything in our lives, and it will affect graduation," Andrea Falletti said. "In a way, it's not going to be celebrating us as much; it's more about what we've done as a community. But that's OK. I'm proud of what we've done here."

As many as 30,000 people were expected for the ceremony for 3,600 graduating seniors, nearly 1,200 graduate students and dozens of students earning associate or advanced degrees. Retired Army Gen. John Abizaid, who once oversaw Operation Iraqi Freedom, is the featured speaker.

While some families may feel unsettled returning to a campus where there has been so much pain, school spokesman Mark Owczarski said they need not because security has been beefed up since the April 16 attack.

Bags will be checked, but guests will not pass through metal detectors or undergo more intrusive security measures. The screening is essentially what Virginia Tech does for a typical home football game, Owczarski said.

In a letter to students' families this week, university President Charles Steger said campus safety was of utmost importance and Virginia Tech was contemplating several changes, even as an independent state panel reviews its handling of the shootings.

"I have read and heard other university presidents and pundits say that this tragedy could have happened on any campus in America. We draw no solace from such observations," Steger wrote. "My hope is that we — and every campus throughout the nation — can learn in the months ahead what happened and why ... to the extent that rational conclusions can be drawn from irrational violence."

Richard Roopan, a business information technology major who posed for photos Thursday in his cap and gown outside Torgersen Hall, said the atmosphere on campus was "a little bit more somber than celebratory."

But after nearly four weeks of mourning, Roopan said he hopes there will be some joy.

"I'm sure there'll be moments within that celebration that you remember what happened and you take the time to pause and reflect on, you know, how lucky you were that you weren't one of those 32 people killed," he said.

"But you have to remember them, also, and what they could have done and their achievements and how, you know, this moment that we have right now has been taken away from them."

Leaving Blacksburg won't be easy, Andrea Falletti said.

"It's brought us closer, but in a different way," she said. "We're all kind of having these same feelings now. It's kind of a special thing."

Associated Press writers Mark Carlson and Sagar Meghani contributed to this report.

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