Admit it: grammar often doesn’t seem to make sense, and sometimes the answer to “why?” is “just because.” This question, however, has an answer, which I will tell you a little further down.
Phrasal verbs are one of the hardest aspect of English grammar because there are so many combinations and different meanings. For example:
Make: to create something new
Up: the direction towards the sky
However, when you put them together, you get totally different meanings and a lot of them:
- Make up: to create something not real (ex. “He made up a story about seeing an alien.”)
- Make up: to do a test or assignment later than usual (ex. “I was sick, so I need to make up the exam.”)
- Make up: to stop fighting with someone (ex. My girlfriend and I were fighting but then we kissed and made up.)
- Make up: to use makeup or some other way of changing your appearance. (ex. “For Halloween, I was made up as a vampire.”)
- Make up: to form a bigger object or thing (ex. “Our department is made up of 10 employees and a director.”)
Of course, that does not explain why we can separate the verb and preposition in some but not others. As in the quote above:
Take after (be like): I take after my father.
I take my father after.
Take off (remove): I take off my coat. OR I take my coat off.
So how do we know? Look at the two examples above. In the first one, I are not really “taking” my father. If you say “I take my father” it is totally different from the meaning of “take after”. However, in the second one, “I take my coat” makes sense. The preposition just tells how we take it, in this case “off”.
Show up means “to appear”, as in “My father showed up at my school.” This is inseparable because taking the preposition “up” away totally changes the meaning.
Show off (display to make people envious), as in “I showed my new car off” is separable because it still has to do with showing something: the preposition only tells how it was showed.
Does this help clarify things? Tell me in the comments or point out exceptions to this rule, if you see any. Anything is okay. Also, email me at firstname.lastname@example.org if you have any other grammar problems you want me to explain.