active voice / passive voice
Whether the subject performs the action or receives it.
Prefer the active voice when the actor matters and you can name it: The committee rejected the bid. Use the passive voice when the receiver of the action is the point, the actor is unknown or unimportant, or naming the actor would distort the emphasis: The bid was rejected. The window was broken overnight. Passive is grammatical English, not a defect. Do not recast every passive sentence. Do not use passive to hide responsibility when the actor should be on the page.
Examples
UseThe editor cut the chapter. (active)
UseThe chapter was cut in the final pass. (passive; the chapter is the point)
AvoidIt was decided that the chapter would be cut. (passive used to dodge who decided)
A sentence is not passive merely because it contains was or were. She was ready is active. Passive needs a past participle of a transitive verb, often with by.