Task: Paraphrasing
Input (English): Question: When exposed to ultraviolet, some substances, such as minerals, glow in characteristic visible wavelengths, a process called this? 
Answer: fluorescence. 
Sentence: When exposed to ultraviolet, some substances, such as minerals, glow in characteristic visible wavelengths, in a process called fluorescence.
Output (English): Fluorescence is the process by which some substances, such a minerals, glow in characteristic visible wavelengths when exposed to ultraviolet.