The second Youth Olympic Games ()in Nanjing this summer

B
首先这是将来时的被动
第二,主语是games,因此是复数（不要受到中文的一场比赛的影响,误任为单数）
单数还是复数,英文里讲究形式上一致,这个单词长成了复数的样子,那你就用复数（大多数情况下）
再问： The first Olympics in modern times _______ in 1896。
A. was taken place B. were held C. was held D. were happened
那这个呢
再答： 按照我的单复数的思路，是选b
D是肯定错，因为happen没有被动