They must do ________ duty and we must do ________.

We must do _______ the Party ________ us. ________,I must do another experiment. He must do his homework now,________? what "must"i/we/you/he/she/they do and what "must not'' i/we a soldier must do bis duty.中文翻译 A soldier must do dis duty Everyone must do one's duty.还是Everyone must do his duty. We must keep our country ________. We must hand in the exercises ,________ We must keep ________ of natur We must do everything we can_____our earth clearer and safer 请教what must they do