Phrasal Verbs. Rules and Tricks [closed]

Here's some useful information:

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.

The short answer is, there's no panacea for phrasal verbs. You just have to learn them.

As people have noted, there is no hard-and-fast rule that will let you instantly understand all phrasal verbs—many of them have idiosyncratic or obscure meanings (and many have more than one). That said, there are plenty of common themes for the different prepositions, in addition to their literal (usually direction-related) meanings. For instance:

• Off often conveys a sense of surprise or something being out of control (go off (=explode), set off, let off (both=cause to explode), make off (=run away), make off with (=steal), )
• On often conveys smoothness or harmony (get on (=have good relations with one another), or continuation (go on (=continue, proceed), carry on (=continue))
• Up often conveys a sense of something being finished or completed (eat up, drink up, settle up) or of inclusion (count up, make up (=comprise)) or of creation (make up (=invent), dream up, set up)
• Out also often conveys a sense of something ending, but in a premature or undesired way (fall out(=cease to be friends), drop out (=leave/be expelled), wipe out (=fall off, e.g. a surfboard)).

This list is far from exhaustive, even for the prepositions listed here; furthermore here are plenty of exceptions to these (for instance to set out to do something means to begin with the aim of doing it—rather than having anything to do with an ending), but as you learn more of these verbs you will get a better feel for the patterns that many of them fall into, and that native speakers often use to coin new ones.

If you were looking for an algorithm for this then check out RainboW Tables as the Wikipedia entry on Phrasal Verbs mention

A phrasal verb often has a meaning which is different from the original verb.

Think of a phrasal verb now as a hash, there's no way for you know to what the original plaintext is based on the hash, the same way you can't know what a phrasal verb means from the original verbs that it is composed of. Rainbow Tables are used for that - it's basically a look-up table for you to piece together the plaintext-hash associations are. For our application you'd use this for your original verb-phrasal verb associations. You could probably start with Ogden's Basic English 850 WOrd List and start off with combinations from that and move to something like this from OWL Purdue. See also this list and also this.