×  I go to my children’s school to pick up them.
√  I go to my children’s school to pick them up.

×  I go to my children’s room to wake up them.
√  I go to my children’s room to wake them up.

When phrasal verbs are transitive (that is, they have a direct object), we can usually separate the two parts. For example, “turn down” is a separable phrasal verb. We can say: ‘turn down my offer’ or ‘turn my offer down’. However, if the direct object is a pronoun (me, you, him, etc.), we  MUST separate the phrasal verb and insert the pronoun between the two parts. See the examples below:

  • Can you stitch on the radio?
  • Can you switch the radio on?
  • Can you switch it on? (We CANNOT say *switch on it.)