北京研彩大孝现代远程教育 ·2.结构 She has(not)left for two hours. Has she left for two hours? Yes,she has.No,she hasn't. ·How long has she left?• 2. 结构 • She has (not) left for two hours. • Has she left for two hours? • Yes, she has. No, she hasn’t. • How long has she left?