盐酸与铝粉反应时，下列措施能使最初的反应速率明显加快的是   [ ]

A.加入少量NaCl固体             

B.盐酸的用量增加一倍   

C.盐酸的用量减半，浓度加倍      

D.向反应混合物中加入少许铜粉

 ______ people went to the concert that was held in Renming Square ______ the night of April 25.

A．Thousands of; in

B．Thousand; on

C．Many thousand; in

D．Thousands of; on