用must或haveto填空
1.I_____finishmyhomeworktoday,becausemyteacheradlkedmetodoit.
2.I_____finishmyhomeworktoday,becauseIwanttofinishitasearlyasIcan.
3.I_____bringanumbrellatoday,becauseit'sgoingtorainthisafternoon.
4.Ifeelthirstynow,soI_____goandbuyabottleofwater.
5.I_____seethedoctor,becauseIamill.