Complex sentence: Modern televisions consist of a display, antenna or radio frequency (RF) input (usually an F connector), and most significantly a television tuner which distinguishes it from a monitor which receives signals that are already processed.
Split into simpler sentences: Modern televisions consist of a display, antenna or radio frequency (RF) input (often an F connector), and a tuner. The existence of a television tuner in a display device distinguishes it from a "monitor"-which receives signals that are already processed.