同义词短语是be sure to，例如：
1.Be sure to wear the correct footwear to prevent injuries to your feet.一定要穿合适的鞋，以免脚受伤。
2.Before leaving the city, be sure to make time for a shopping trip离开城市之前，一定要留出时间去买些东西。
3.Be sure to give your family my regards.务必代我向你的家人问好。
