Final answer:
The correct word to describe a person who talks a great deal and easily is 'voluble'. This term is often used to characterize someone known for their fluency in speech.
Step-by-step explanation:
A voluble person talks a great deal and with immense ease. This adjective is used to describe someone who is fluent and talks a lot, sometimes to the point of being overwhelming. It is not to be confused with 'vehemently,' which relates to showing strong feeling or passion; 'vast,' which describes something of very great extent or size; or 'vagrant,' which refers to a person without a settled home or regular work.