phrasal verbs
When a verb and an adverb particle go together go together,They form a phrasal verb.
Common adverb particles in phrasal verbs are across,away,down,in,off,on,out,through,up
the meaning of the phrasal verb may be difficult to guess from the meaning of its two words.
john and ann broke up after going out for three years.(=no longer dated each other)
My father gave up smoking.(=stopped)
We found out the answer.(=discovered)
Sometimes the same combination can have two meanings
Take off your sweater.(=remove)
The plane took off on time.(go into the air)