Ответ:

  1. His sister and her friends hang out at the harbour at weekends. Hang out — проводить время.
  2. I've run out of bread, so I'll buy some after work. Run out of — закончиться, исчерпать запас.
  3. If a burglar breaks into your flat, you should hand over your money. Hand over — передать.
  4. She saw a policeman running after a robber. Run after — бежать за кем-либо.
  5. Tom ran into an old friend when he was at the shopping centre. Run into — случайно встретить.

Ответ: 16 — out; 17 — of; 18 — over; 19 — after; 20 — into.