I was giving a talk to a large group of people，the same talk I to half a dozen other
groups.
A.was giving B.am giving
C.had given D.have given
I was giving a talk to a large group of people，the same talk I to half a dozen other
groups.
A.was giving B.am giving
C.had given D.have given
C
考查时态的用法。因前一句的时态是过去时，而我给其他六个组做报告发生在给许多人做报告之前，故用过去完成时态。