Question

By studying the suffix, the reader can determine that “impetuous” most likely means

Answer 1

By studying the suffix from Latin impetus means "an impulse", so impetuous most likely means a person that acts quickly and without thought or care, by impulse and the heat of the moment.

Answer 2

A suffix, also known as ending, is an affix or morpheme which is attached after the root of a word to form a new word.  

Specifically,  the suffix -ous is a suffix that forms adjectives which expresses that a certain person or object possesses a given quality. Therefore, by studying this suffix in the word “impetuous”, the reader can determine that such word is an adjective which means possessing great impetus,  characterized by sudden actions.