our earth, or else it will be no longer fit for us to live on

It’s more than half a century ________ mygrandfather joined the Party and became a servant to the people.

he debt problem worsening, it is going to be a______ test for EU to help Greece out of trouble.

When she come home she found her house were _____and everything _____ [ ]

If one has never tasted bitter, he or she does not understand _____ is sweet.[ ]