题目

The news that Xiamen Xiang’an Tunnel, China’s first undersea tunnel, has been put into traffic excites us greatly, ______?    A. doesn’t it                   B. does it                      C. do they                    D. don’t they 答案：AIt _______ long before we ______ the result of the experiment. A．will not be; will know B．is; will know C．will not be; know D．is; know