---What is our earth like ________from the moon? ---Well, our earth, with water ________ 70% of its surface, appears as a "blue ball".
—What time do we have to be at the gate? —_______ passengers start to board the plane.
Simon thought his computer was broken _______ his little brother pointed out that he had forgotten to turn it on.
Don’t be afraid of asking for help _______ it is needed.
Food shortage will long be a worldwide problem _______ much has been done to supply enough for everyone.
I do every single bit of housework _______ my husband Bob just does the dishes now and then.