We are all working hard __this math problem?A.in B.at C.with

We are all working hard __this math problem?A.in B.at C.with They are all working hard ( ) at English. Lily is working ___ the maths problem.A.at B.in C.on D.of I am working hard ( ）French.A.at B.for C.in D.on His father works hard () A.at all day B.in all day C.all day We ( ) school today ,Miss Gao.A、are all at B、all are at C、ar The workers____very hard.A.all work B.are all at work C.work Could you help me___out the math problem? A.working B.work C we ( ) in the classroom.A all B are C are all D all are She is not interested ___ math at all.A.for B.in C.to D.abou The students are working ____ a model plane.A.to B.in C.with we have sweaters ( )all colors ( )￥50 A.in 、at B、at、in C、in、