三个连续整数中，若n是大小居中的一个，则这三个连续整数的和是______．
n-1+n+n+1=3n．
24. Only when the meeting began _______ that he had left his papers at his office.
A．will he realize
B．he did realize
C．did he realize
D．should he realize
在实际生产中，调节阀在检修后调校应注意些什么？
