Phrasal verbs are combinations of a verb and a preposition or adverb (or both).
Here are a few examples:
* look up (to search for information)
* give up (to stop trying)
* put off (to postpone)
* get along (to have a good relationship)
* take off (to leave)
* turn down (to refuse)
Phrasal verbs can be tricky because they often have different meanings than the individual words themselves.