Last November, Christopher Sharikas pleaded guilty to carjacking an Arlington woman's Mitsubishi Eclipse, plunging a knife into her back and then stealing her purse. But at his sentencing yesterday, the teenager denied stabbing her and blamed her for refusing to turn over her car keys.

"It just went from 60 years to life!" Arlington Circuit Court Judge Paul F. Sheridan said angrily from the bench before sentencing Sharikas, who was 17 when he stole Amy Greenwood's car a year ago. "That is so insulting to the victim!"

Although Virginia's voluntary sentencing guidelines call for seven to 11 years in prison in his case, Sheridan sentenced Sharikas, now 18, to the maximum: two life terms for the carjacking and robbery, five years for the stabbing, 20 years for maliciously wounding Greenwood, and five years for being a convicted felon with a concealed weapon.

Before yesterday's sentencing, defense attorney Sherman Everlof urged the judge to follow the guidelines and place his young client in a facility where he could receive help for psychological problems.

But the prosecutor, Assistant Commonwealth's Attorney Theo Stamos, asked the judge instead to give Sharikas a longer sentence that would "keep us safe."

"He is the person in the community that everyone worries about when they're driving alone," Stamos told the judge. "He is the kind of person who makes us feel unsafe."

When she was carjacked, Greenwood was an intern working in the prosecutor's office with Stamos. Now a 25-year-old law clerk for a Montgomery County Circuit Court judge, Greenwood returned yesterday to the courthouse where she had prosecuted dozens of criminal cases -- this time as the victim on the witness stand.

Last April 10, after leaving work at the Arlington courthouse and running an errand, Greenwood went to a late-afternoon doctor's appointment in Falls Church. As she got out of her car in the clinic parking lot about 5:45 p.m., Sharikas came up behind her with a knife and demanded her car keys, which she immediately surrendered, she said.

As she stepped away from him, Greenwood told the riveted courtroom, the teenager "punched" her hard in the back.

"He demanded my purse, and I gave it to him," Greenwood said from the stand, slowly reading aloud a letter she had written to the judge.

"As he struggled to get into my car, I collapsed onto the sidewalk, strewing the papers in my hand all over the ground," she said. "I tried to get up, but I couldn't. The pain in my back and my chest was too intense."

No one, not even Greenwood, realized she had been stabbed until she got to Columbia Arlington Hospital. Meanwhile, her boyfriend, Alan Lowrey, an Arlington detective, was paged in the District and came racing to her side.

But as he drove on Interstate 66 in his cruiser, she told the court, Lowrey recognized his girlfriend's Mitsubishi whizzing past him, with a stranger behind the wheel. Believing she was being cared for at the hospital, the officer chased the suspect until a radio call told him to get to the hospital right away.

"The paramedics and emergency room staff began to lift me off the stretcher when I heard: Oh my God! This woman has been stabbed!' " Greenwood said.

Police caught Sharikas later that night, with the bloody knife in the car, when he crashed in Frederick, Md. Greenwood, whose liver was punctured with the knife, has recovered from most of her physical injuries but is still haunted by what happened.

"I've prosecuted cases, and I've been a victim," Greenwood said outside the courtroom. "You don't realize the true impact of crime until you actually live it."