"It was dusk" is passive.  That's the part that should be changed,
IMO.

Passive voice deals with changing the subject of the sentence.  As in:

"The bus hit the old woman." Subject is 'the bus', 'old woman' is the
direct object.  This is active voice.

"The old woman was hit by the bus."  'old woman' is both subject and
object. This is passive voice.

(may have some of the terms wrong, but the principle is right, i think)

There's only one noun (or more precisely, no object) in "it was dark", and
hence the concept of active vs. passive voice is not applicable.

As others have noted, this doesn't mean it's the best way to word the
sentence.

Chris Burke

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