Wouldn’t it be wonderful world if all nations lived in peace with one another?A. the; /B

问题补充：

Wouldn’t it be wonderful world if all nations lived in peace with one another?

A. the; /

B. a; /

C. the; the

D. a; the

答案：

A. the; /

(答案→)B. a; /

C. the; the

D. a; the

解析：world表示“世界”时,通常在其前加定冠词the;但world前面或后面有定语修饰时,通常要用不定冠词a。in peace是固定用法，意思是平安，和平。