Here are the completed sentences:

1. My son made the decision to spend less time playing games. (CUT)
→ My son decided **to cut down on** playing games.

2. Jimmy wonders what she should buy for his parents in Ha Dong Silk Village. (TO)
→ Jimmy wonders **what to buy** for his parents in Ha Dong Silk Village.

3. She is thinking of booking a one-month holiday in Viet Nam so that she can visit many handicraft villages. (IF)
→ If she **goes on holiday** in Viet Nam, she can visit many handicraft villages.

4. We had no food left, nevertheless we continued to walk. (RUN)
→ We **ran out of** food, nevertheless we carried on walking.

5. I met my old friend unexpectedly when we were delayed at the airport. (BUMP/HOLD)
→ I **bumped into** my old friend when we were **held up** at the airport.

6. Kate has quit her career as a manager and she can't wait to go to India. (WALK/LOOK)
→ Kate **has walked away from** her career as a manager and she is **looking forward to** India.