What should we do--the Earth for our future?It's very import

What should we do__the Earth for our future?It's very important to__it.
A.to protect;stop polluting B.to protect;stop to pollute
Would you like__coffe?NO,thanks.there__still some in my cup.A any;are B.any;were
I failed my english exam again!i really don't know how__it well.Well,you'd better spend more time __it every day.
A.to learn;read B.to learn,reading