Complex sentence: Back in her world Dr Lee is using a sound device and is scanning the area, she reappears behind him in a flash of light and goes unnoticed until she says his name, which in shock he drops the sound device and feedback screeches though the earphones.
Split into simpler sentences: Back in her world Dr Lee is using a sound device and is scanning the area, she reappears behind him in a flash of light and goes unnoticed until she says his name. In shock he drops the sound device and feedback screeches though the earphones.