The world . Things never stay the same.
A. changed
B. is changing
C. was changing
D. will change
网友回答
A. changed
(答案→)B. is changing
C. was changing
D. will change
解析：本题考查现在进行时的基本用法。本题的含义为世界一直在改变，事物从来不保持一样。根据句意可知本题使用现在进行时，结构为be+动词的现在分词，本题主语为单数第三人称，故用is，故本题空格处填is changing，故本题选B。