根据下列各句空白之后的汉语提示词及首字母提示，在答题卡指定区域的横线上写出对应单词的正确形式，每空只写一词。(注意：请写出完整的单词)
Michael Jackson made a great ______ (贡献) to the world’s popular music.
The majority of the ______ (市民)are against the project.
These ______(古代的) buildings must be preserved.
She dropped studies because of ______(贫穷).
What do you thing is the most important ______ (发明) in the 20^th century?
The two leaders ______(交换) their ideas about this problem at the meeting held last month.
His heart is beating______ (猛烈地) while waiting for the result...
People are ______ (抱怨)about high prices.
Why do you want to ______ (辞职)your position as secretary?
The world's resources are limited, so the reusable resourcesshould be______ (循环利用).