1.   At first, it was a few popping sounds, then the shooting became faster, steadier.

2.   But mass shootings have become an American tradition.

3.   Drive-by shootings became commonplace in many poor neighborhoods where the cheap-drug trade flourished.

4.   He had also survived the slow slide of a working-class neighborhood into a tough one, where neighbors said nighttime shootings had slowly become a way of life.

5.   If any doubt remains that school shootings have become a trend, this incident ended the debate.

6.   Meanwhile, foul shooting has become a mental problem for Mourning.

7.   Mass shootings have become a common enough part of American life that many people are inured to reports of yet another crazed gunman run amok.

8.   So free throwing shooting became recreation and therapy.

9.   Such random shootings have become rare in recent years.

10.   The bad shooting became contagious.