A computer is so useful a machine ________ we can use everywhere.
Why don’t you just your own business and leave me alone?
You have made a mistake --- you have _______ the letter “e”.
News reports say peace talks between the two countries have broken down ______ no agreement reached.
—Why didn’t you try your best to get on the bus?—I tried to , but _______ I could, it started moving.
They were walking along the shore _______ a huge wave appeared out of nowhere, sweeping them out to sea.