In the exam,the _____ you are,the ____ mistakes you’ll make.

In the exam,the _____ you are,the ____ mistakes you'll make.
A careful;little
B more careful;less
C more careful;few
D more careful;fewer
Do you often hear John _____ in his room.
Listen!Now we can hear him ____ in his room.
A sing;to sing
B singing;singing
C sing;singing
D to sing;singing
How about some drinks?
_______
A yes,great
B no,I can't
C yes,you're welcome
D yes,place
Will you please put your things away?
_____
A that's all right
B it doesn't matter
C certainly
D all is right
Will you join us for lunch?
_____
A no,I won't
B yes,with pleasure
C yes,please
D yes,help yourself
要理由的说

1、B
你越细心,在考试中犯的错误就越少.
“越…越…”无疑要用比较级,careful的比较级当然是more careful,看共有三项有more careful也知道它必选；more与less相对
2、C
第一空to sing肯定不对,这里用不着不定式；hear sb. do sth.因此选sing；第二空现在时singing.
3、A
不仅赞同提问者的提议,而且是有礼貌的答复.
4、C
A和B都不是回答这个问题的,是“没事, 我不介意”的意思,礼貌上不符合；D一看就不对.
5、B
——你会和我们共进午餐吗?
——是的,我很荣幸.
A太不礼貌了,C回答不对,D是多吃点的意思.