Description:
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Something wrong with the introduction sentence on "Program Execution Functions" section (http://php.net/exec).

Reproduce code:
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Visit http://php.net/exec

Expected result:
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Maybe something like:
"Those functions provide means to execute commands on the system itself, and means to secure such commands."

Actual result:
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"Those functions provides means to executes commands on the system itself, and means secure such commands."