题干
Jack usually __________ homework after school, but now he __________ a book.
A：do; is reading
B：does; reads
C：does; is reading
D：do; reads
答案(点此获取答案解析）
C
Jack usually __________ homework after school, but now he __________ a book.
A：do; is reading
B：does; reads
C：does; is reading
D：do; reads
，则下列代数式中值最大的是