谈判前的计划不包括()
A.最佳成果
B.底线
C.条件
D.试探
参考答案:D
-Be careful! You might fall into the water.
-Thank you. I____.I______ so close to the pool.
A.didn't know; am standing
B.don't know; am standing
C.didn’t know; was standing
D.didn't know;Would stand
简述同步网的时钟等级和设置。