Tom went to see his grandparents with his father. In the train Tom often put his head out of the window. His father said, “Tom, don’t put your head out of the window.” But Tom went on putting his head out of the window.

His father took Tom’s hat quietly and hid it behind his back and said to Tom, “You see your hat is gone.” Tom was afraid. His father said, “Well, whistle（吹口哨）once. Maybe your hat will come back.” Tom whistled. His father put his hat on Tom’s head quickly. “Oh! It’s wonderful!” Tom laughed and said. He quickly took his father’s hat and threw it out of the window. “Now it’s your turn to whistle, Dad!” he said happily.

小题1:Tom went to see his grandparents with his father __________.

A．by bus

B．by train

C．by plane

D．by ship小题2:Tom often put ___________ out of the window.

A．his hat

B．his father’s hat

C．his head

D．his father’s head小题3:____________ and his hat was on his head.

A．Tom whistled

B．His father whistled

C．Both of them whistled

D．The conductor（售票员）whistled小题4:Tom took his father’s hat and ___________.

A．hid behind his back

B．threw it out of the window

C．put in under his seat

D．put it on his own head小题5:At last Tom’s father’s hat _____________.

A．Came back

B．lost

C．In his head

D．in Tom's head

孕妇硬膜外阻滞平面扩散较广的主要机制是()

A．体弱平面易扩散

B．硬膜外间隙是负压

C．硬膜外间隙是正压

D．硬膜外血管充盈间隙变小

E．通气量大