选择正确的答案，将其序号填入题前括号里

(C)David is playing___basketball in the playground.
A.a B.the C./ Dat
(B)A:Are you cold?B:_____.
A.Yes,she is. B.Yes,I am. C.No,I am. D.Yes,I'm not.
(A)Look!He___their mother do the housework.
A.is helping B.are help C.is help D.is helpping
(C)__are the boys doing?They are singing in the room.
A.Who B.How C.What D.Where
(A)Don't talk here.My mother__.
A.is sleeping B.are sleeping C.sleeping D.sleep
(B)Danny___.Don't call him.
A.is writeing B.is writing C.play the D.writes
(A)A:When ___he___back?B.Sorry,I don't know.
A.does,come B.are,coming C.is,come D.is,coming
(B)The children___football.
A.is playing B.are playing C.play the D.play a