美容美发场所化妆品、消毒产品储藏应遵循（）原则，变质或过期产品应及时清除并销毁。
参考答案：先进先出
— Is Lily good at singing? —Yes , she is．We often hear her_______ in the next room．
A．sing
B．to sing
C．sang
D．Sings
--Mom, I can't find my new T-shirt.
--Oh, honey, it__________after you went to see AVATAR. It is still in the dryer.
A．has been washing
B．has washed
C．was to be washed
D．was washed
