A prefix. (Example: Patient. The prefix is Im-. So, if you add Im- to Patient, you get Impatient.)
A group of postal letters is called a mail or a batch of mail.
a small group (5 letters)
A word. Many groups of letters is called a sentence(:
prefix
prefix
A group of trees is called a wood from which a forest area could be called a woodland.
Group of A4 sheet is called as ream.......
set
Company, ensemble.
Acronym
it is called simply a group of kings and queens!!
It would be placed in group 17 of non-metals.