Grammatically Correct: The writer's essential guide to punctuation ...

Active Versus
Passive Voice
Grarmnatically speaking, voice refers to whether the subject of a
sentence is on the performing or the receiving end of the action. In
sentences written in the active voice, the subject is the doer: Bob
caught the Frisbee in his teeth (subject is Bob). In sentences written
in the passive voice, the subject is acted upon: The Frisbee was
caught in Bob's teeth (subject is the Frisbee). In a passive construction,
the person or object that is actually performing the action may
be referred to in the sentence, but is not the focus of it.
The topic of voice is addressed here rather than in the chapter
on grammar because misuses of voice do not constitute actual errors,
but do affect tone, emphasis and readability-all of which are issues
of style, not of right and wrong.
ADVANTAGES OF THE ACTIVE VOICE
Some grammar teachers issue a straight dictum to always use the
active voice, never the passive. This overly simplistic advice would
be better phrased as use the active voice as a general rule, and
use the passive voice only if there's a specific reason to do so.
The active voice has definite advantages over the passive: It's more
direct and concise, and it can make your writing appear more vigorous
and confident. The passive voice may sound clumsy, plodding
or overly cautious in contrast. For example, compare the following
sets of sentences:
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PASSIVE: When the Fl key is pressed, help information is shown.
MORE DIRECT: When you press the Fl key, help information appears.
EVEN MORE DIRECT: Press the Fl key to see help information.