외출할 때는 꼭 모자를 쓰도록 해 I saw this example sentence (with the translation below): 외출할 때는 꼭 모자를 쓰도록 해 You have to make sure to wear a hat when going outside. 1) Could I use 써야 해 instead of 쓰도록 해 to get the same meaning, "You have to..."? 2) What is the purpose of 꼭 in this sentence? I know it can mean "exactly" or "tightly", "surely", etc. But in this sentence, does it mean to wear the hat "tightly"? Or does it mean "surely" as in "make sure"? 감사합니다!