verb
1
BAD : The day after his 35th birthday, he shot 22 innocent people to death.
GOOD : The day after his 35th birthday, he shot dead 22 innocent people.
BAD : The prisoners were either hanged or shot to death.
GOOD : The prisoners were either hanged or shot.
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beat/hack/stab sb to death BUT shoot sb dead or shoot and kill sb (NOT shoot sb to death ): 'Hector Petersen was shot dead by South African police in June 1976.'
Note that shoot by itself can mean 'shoot and kill': 'After shooting his victims, he buried the bodies in a nearby field.'
2
BAD : Someone in the crowd ran up and shot a gun to the president.
GOOD : Someone in the crowd ran up and fired a gun at the president.
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fire a gun ( at sb ), NOT shoot a gun : 'As part of the celebration they drove through the streets firing guns in the air.'
Note the alternative: 'Someone in the crowd ran up and fired at the president.'