It.s busy during summer,so buying or reserving tickets in advance is recommended.
【A】：这里夏天很忙碌，所以建议提前买好或预订好票
【B】：这里夏天很忙碌，所以购买或提前预订票被建议。
【C】：这里夏天很忙碌，所以建议买优先票。