根据句意及汉语提示完成单词.

① Have you____ (曾经)taken the subway alone late at night?  

②She won first____ (奖)in the 100-meter race.  

③It was his____ (梦想)to play football for his country.  

④We can not____ (付得起)the cost of two telephones.  

⑤It was a____ (遗憾)that you missed the party.  

已知数列$\left\{a_n\right\}$，若点$\left(n,a_n\right)$$(n\in N*)$均在直线$y-2=k\left(x-5\right)$上，则数列$\left\{a_n\right\}$的前9项和$S_9$等于（  ）

①正确，作为社会成员，这是一种推动社会建设的行为

②错误，中学生只要好好学习，多参加公益活动即可

③正确，青少年要培养自己的使命感

④错误，青少年学生无权管理国家事务