The Dragon Boat Festival is coming. Please tell your children to 小题1: care if they want to swim and be friendly 小题2: others while playing. Better not agree them to go out by 小题3:at night. Also, playing computer games 小题4: much will make them feel uncomfortable. Most importantly, remind them to finish their 小题5: on time.

Have a good holiday!

每个投资者的无差异曲线形成密布整个平面且可以相交的曲线簇。( )