问题补充：
--- Where is your grandpa now?
--- He newspaper in the living room.
A. read
B. is reading
C. was reading
D. reads
答案：
A. read
(答案→)B. is reading
C. was reading
D. reads
解析：now通常表示现在进行时，进行时的结构是be+动词的现在分词（doing），主语为
第三人称，所以be用is，所以本题选B,is reading。
