Phrasal verbs consists of a basic verb + another word or words. The two or three words that make up a phrasal verb form a short 'phrase' - which is why we call them 'phrasal verbs'.
Phrasal Verb:
speak out (on something)
Meaning:
to say something frankly and directly.
Example:
This law is wrong, and I intend to speak out on it until it is repealed.
Phrasal verbs, also called two-word verbs, are idiomatic expressions wherein the second element of the verb (the adverb or particle) is not necessarily predictable.