Jenna fell in the parking lot and blacked ___.
out --> to black out (to faint, lose consciousness)
That company does not carry ___ tests on animals.
out ==> to carry out (to perform or conduct a test, an experiment, etc.)
When he saw the bear, he backed ___ in fright.
away --> to back away (to move backwards, in fear or dislike)
I advise ___ walking alone in this neighborhood.
against --> advise against (to recommend not doing something)
I must brush ___ on my English before going to NYC next month.
up --> to brush up on sth (to improve, refresh one's knowledge of something)
It all boils ___ to who has more power.
down --> to boil down (to be summarized as)
He applied ___ a scholarship for next semester.
for --> to apply for (to make a formal request for something; job)
The facts in the case just don't add ___ .
up --> to add up (to make sense)
She needs to work fewer hours. Otherwise she will burn ___.
out --> to burn out (to become exhausted from over-working)