How to use "monitor" in a sentence

The monitor went dark.

She told him about the bizarre things that had been happening to her lately: the messages on Danny's chalkboard; the wreckage she'd found in the boy's room; the hateful, taunting words that appeared in the computer lists and on the monitor.

The cold spell won't last." He squinted into the smaller room, where the boy lay motionless on a hospital bed, under a white sheet and yellow blanket, trailing monitor wires

A camera and two-way video communications monitor were mounted in the left-hand wall of the vestibule

Beside the monitor was a lighted glass plate against which the visitor was supposed to place his right hand, palm-down, within the existing outline of a hand