split make up

Today, a teacher told me that we cannot spilt the phrasal verb "make up", in its use below.

He said...

make up your mind (correct)
make your mind up (incorrect)

To me, they both sound correct.

I only like the first, but both can be found in the dictionaries, so I think both are ok.

I think the "correct" form is much more common, but I don't see where the "incorrect" form would cause confusion. It's unclear whether or not I'd ever say the "incorrect" form in spontaneous conversation, though.

<<make up your mind (correct)
make your mind up (incorrect)
>>

Both are correct, but the twythe one (i.e. the second one) can become confused with "make something up" i.e. to fabricate something, in this case, your mind:

so it can possibly mean two things:
Make your mind up = make up your mind/decide
Make your mind up = fabricate your thinking/thoughts

Even though I am wis no one would actually confuse it for such, the construction is analog to others where it would (eg. Make a story up, make it up, etc)

Sounds like your teacher is trying to teach you strict grammar rules rather than how people actually use the language. The second version seems considerably more familiar to me. Learn the language how it's used.

Learn the language how it's used.

Like this? ;-P

a reight bobby dazzler
a reight gud sooart
Ah wor fair starved
allus at t’ last push up
goin’ dahn t’ nick
livin’ tally / ower t’ brush
popped ‘is cloggs
put wood i’th’oil
tek a good likeness

Your teacher is incorrect. There are separable phrasal verbs and inseparable phrasal verbs.

http://grammar.ccc.commnet.edu/grammar/phrasals.htm

"Make up" falls in the separable category, as used in this timeless little ditty:

"If you can't make your mind up,
We'll never get started.
And I don't wanna wind up
Being parted, broken-hearted."

Other separable phrasal verbs:

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She picked up the kids from school.
She picked the kids up from school.