Cho dạng đúng của từ trong ngoặc:
1. He goes to school by bike ................... (safe)
2. Life in the city is much .................... from life in the country. (differ)
3. I go to the .......... center once a week. (amuse)
4. Lan enjoys taking part in outdoor .................. with her friends. (act)
5. Videos can help the police when there's a .............. (rob)
6. Some of the ............... of computer games are as young as 14 or 15. (invent)