情态动词must/have to用法 — 英语填空题
题目
Last Saturday, Linda wanted to buy a second-hand bike, but she had forgotten her wallet at home. She ___ go back home to get it because the seller would only take cash. Her mother said, "You ___ always check your bag before leaving." 用 must 或 have to 的适当形式填空（每空一词）。