"I was sitting there, trying to figure out if this is real," said Habtu, who could not believe that someone was shooting real bullets at her classmates. "I thought it was fake, and then, when people were falling on the floor, and people started ducking, it was like, wow, this is real."
Habtu, who was sitting front and center, was shot twice, once in the face and once in the wrist. One bullet went through her jaw and lodged in her tongue, stopping just one millimeter from her brainstem. Had it gone any farther, she would most likely be dead or paralyzed.
As Habtu huddled under her desk, waiting for Cho to leave the room, students around her were attacked. Sterne was hit twice in the leg, a bullet hit McQuade in the face and shattered his jaw, O'Dell was injured in the right arm and Carney was shot in the hand as she crouched under her desk, trying to shield her face.
The survivors lay on the ground playing dead until Cho left the room, and then Carney, O'Dell and Erin Sheehan, who made it through the attack uninjured, positioned themselves behind the door to prevent Cho from re-entering the classroom.
"I was crouched down behind the door, and we used all of our might to hold it, to close it as much as we could, and he tried a couple of times to get back in," Carney said. When Cho could not open the door again, he fired shots through the door before giving up and moving on.
When police arrived, still in search of the shooter, Cho had already killed himself and was lying on the floor at the front of the German class. Bishop and four students were killed.
In the French class, 12 had died by the time the shooting had ended, including the instructor, Jocelyn Couture-Nowak. Too weak and injured to walk, Goddard and Heeger were carried out of French class. The photo of them being lifted by police on the way out of the building became one of the most iconic images of the day's tragic events.
Despite the nation's curiosity about what happened in those Virginia Tech classrooms, the survivors have said their memories of those moments are sketchy at best. McQuade said that he has no memory of the day's events at all and that he did not know what happened for three weeks after he woke up in the hospital.
"It was complete and utter shock," said Heeger. "There was just a blur, and then it was 'Please, please, get us out of here.'"
Heeger and other survivors whom ABC News spoke to have spent much of the last four months trying to put April 16 behind them, working instead on moving forward with their lives and their recoveries. They have undergone multiple surgeries, logged countless hours in rehabilitation therapy and reached out to one another to try to heal emotionally.
McQuade, who will have five bullet fragments in his head and neck for the rest of his life, keeps a positive attitude, despite the fact that the right side of his face remains paralyzed and expressionless. "I came out of it relatively unscarred and I'm thankful for that," he said.
Just five days after the shooting, Carney left the hospital to be the maid of honor at her sister's wedding. "They literally pulled the IV out of my arm," she said with a smile. She has spent the summer doing a variety of therapies to strengthen the fingers on her left hand, while also retraining herself to write with her right.