PHRASAL: to act like (non-separable)
MEANING: to behave like ___; to act in a certain manner
EXAMPLE: My brother was acting like a wild animal last night.
               Mary acts like she likes me, but I know she's only pretending.

PHRASAL: to act up (non-separable)
MEANING: to behave badly
EXAMPLE: The children in class acted up when the teacher left the room.

PHRASAL: to act up (non-separable)
MEANING: to work improperly
EXAMPLE: My computer has been acting up lately. It needs to be repaired.

PHRASAL: to add on (separable)
MEANING: to increase something
EXAMPLE: Our house was too small, so we added on another bedroom.

PHRASAL: to add up (separable)
MEANING: to find the amount
EXAMPLE: I don't know how much tax to pay. I'll have to add the tax up.

PHRASAL: to add up to (non-separable)
MEANING: to find the total
EXAMPLE: The clothes add up to $550.00; that's a lot of money!

PHRASAL: to ask out (separable)
MEANING: to invite someone on a date
EXAMPLE: Brad asked Jennifer out. They're going to a movie.