Question

change these sentences into positive (+), negative (-) or question (?)

1- They must clean their class eveyday

-

-

Answer 1

(+) They must clean their class everyday

(-) They mustn't clean their class everyday

(?) Do they have to clean their clas everyday?

Answer 2

(+) They must clean their class everyday.

(-) They mustn't clean their class everyday.

(?) Must they clean their class everyday?