One of the great things about science is that it has taught us to be __________ about surface appearances. The world seems flat, but it is, in fact, round.
You may catch up with others __________ you work a little harder.
Without electricity human life __________ quite different today.
Gunpowder is generally believed __________ in ancient China.
It was __________ great shock to the world that a French airplane got missing over __________ Atlantic Ocean on June 1st, 2009.
I feel nervous before the exam. -- __________. It won’t be too difficult for you to pass.