mood The form of a verb that shows the writer’s attitude toward a statement.
voice The form of a verb that indicates (active) or deemphasizes (passive) the performer of the action.
The original sentence shifts from the indicative mood (I entered ), used for statements and questions, to the subjunctive mood (I could know), used to indicate hypothetical, impossible, or unlikely conditions.
Although mood and voice may need to change to fit the context of a sentence, unneeded shifts may seem inconsistent. (See also G5-c on mood, G5-d on voice, and T2-a on conditional clauses.)
Change the verbs in a conditional clause or passage to a consistent mood.
Make the verbs in a passage consistent, preferably using the active voice.
(See also G5-d.)