（）是一种将低温物体中的热能传递至高温物体中的一种装置。
A.水泵
B.热泵
C.气泵
D.高压泵
参考答案：B
As the director can't come to the reception, I'm representing the company ______.
A．on his account
B．on his behalf
C．for his part
D．in his interest
附肢和翅不贴附在身体上，可以活动，同时腹节间可以自由活动，这种蛹为（）
A、离蛹
B、被蛹
C、围蛹
D、茧蛹
