空气滤清器堵塞清除方法？
参考答案：清扫滤清器芯子或按需更换。
会计凭证的传递必须做到准确及时、手续严密、办妥交接、先内后外、先急后缓。
Everybody, men and women, old and young, _____ sports and games.
A．enjoy
B．were enjoying
C．enjoys
D．is enjoyed
