64S继电半自动闭塞电路中JXJ的作用是（）。
参考答案：接受通知出发信号
As time _____ slowly, he was better and better. [ ]
A. went out
B. went up
C. went by
D. went down
以经济建设为中心是兴国之要，（）仍是解决我国所有问题的关键。
A、发展
B、改革
C、创新
D、人才
