1.-I guess you are ( ) teacher.
-NO.But I'm interested in ( )education of young children.
A.a;the B.the;/ C./;the D.a;an
2.-I couldn't help ( ) the tent because I was not free at that time.
A.to put up B.putting up C.to putting uo D.having put up
3.-How much did you want for that?
-( )
A.I did it for free B.I did nothing for it C.I spent 5 yuan D.I paid 5 yuan