Are a more informal way to express something.-2. can be substituted with stand alone verbs.-3. can have more than eight meanings.-phrasal verbs can often be the more informal, colloquial choice e.g. the postphone a meeting vs to to put off a meeting but that is not to say they cannot be used in formal contexts. native speakers tend to know when and where to use them without thinking about it and often they are just another way to express something e.g to fill out (or fill in!) a form vs. to complete a form.
they can usually be substituted with other verbs but not always appropriately, for example i awoke and arose early this morning vs. i woke up and got up early this morning.
as suggested earlier, they can have many meanings, generally between two and eight.
they are definitely not easy for foreigners to use or understand and reducing the amount of them we use in spoken and written communication eases the burden on the non native speaker who might spend years learning english and never get to grips with all of them.
