Eliminate passive voice by making the subject do the action. You can shift the focus of the sentence from the direct or indirect object to the actor. For example, you can transform the following sentence from passive to active voice. Passive: The tree was cut down by the man.
The laws of time did not allow men of color to practice law.
She's able to be happy at some points. "Turning on the light upstairs" is a way to "turn on" happiness.