问题补充：
The manager was worried about the press conference his assistant in his place but luckily, everything was going on smoothly.
A. gave
B. gives
C. was giving
D. had given
答案：
A. gave
B. gives
(答案→)C. was giving
D. had given
解析：考查时态：从题意“经理很担心助手正在代他参加的新闻发布会，但幸运的是，一切进展顺利，可知，give这一动作和was worried about同时存在，还有everything was going on，说明是过去正在进行，根据题意可知应用过去进行时。选C。
