Phrasal Verbs and other multi-word verbs

Phrasal verbs are part of a large group of verbs called "multi-word verbs". Phrasal verbs and other multi-word verbs are an important part of the English language. Multi-word verbs, including phrasal verbs, are very common, especially in spoken English. A multi-word verb is a verb like "pick up", "turn on" or "get on with". For convenience, many people refer to all multi-word verbs as phrasal verbs. These verbs consist of a basic verb + another word or words. The other word(s) can be prepositions and/or adverbs. The two or three words that make up multi-word verbs form a short "phrase" - which is why these verbs are often all called "phrasal verbs".
The important thing to remember is that a multi-word verb is still a verb. "Get" is a verb. "Get up", is also a verb, a different verb. "Get" and "get up" are two different verbs. They do not have the same meaning. So you should treat each multi-word verb as a separate verb, and learn it like any other verb. Look at these examples. You can see that there are three types of multi-word verb:

 - single-word verb :

look

direct your eyes in a certain direction

You must look before you leap.

- multi-word verbs : 
1-

prepositional verbs

look after

take care of

Who is looking after the baby?

2-

phrasal verbs

look up

search for and find information in a reference book

You can look up my number in the telephone directory.

3-

phrasal-prepositional verbs

look forward to

anticipate with pleasure

I look forward to meeting you.