Independent memory in most languages is an important part of the word, which is also called the root or element (root), such as bean, beans in slowly, slow in use in useful, etc.
An independent unit in the most important part of which is called radical or element (root) such as bean in beans, slow in slowly, use a useful example.
Free morphemes in language most often is an important part of the word, which is called the root or the elements (root) such as bean, in beans slow in slowly. Use in useful, etc.