Phrasal verbs
A phrasal verb consists of a verb and an adverb particle, Adverb particles are very much like prepositions, and some teachers call them prepositions. Some called them adverb particles to distinguish them from the prepositions that were used after certain verbs in the last lesson. You can see the difference between prepositions and adverb particles in the following sentences, where the adverb particles are underlined and the prepositions are italicized.
The enemy blew up the bridge with dynamite.
The secretary took down the messag in ink.
Come back with me to my office.
He picked up the coats and hung them up on the pegs.
One should notice from these sentences that hte adverb particle belongs very closely to the verb. It has almost no meaning on its own, nor very often has the verb. It has almost no meaning on its own, nor very often has the verb. Sometimes it is impossible to guess the meaning of the phrasal verb even if you know both verb and particle.
In the above sentences, blew up has very little to do with blowing; it means to destroy. In the same way, took down means wrote, and picked up means lifted.
We must, then think of phrasal verb as one unit- one single verb. It is easy to do this if we realize that phrasal verbs often have the same meaning as single verbs, example.
to blow up = to destroy
to go away = to leave
to pick out = to choose