If you swim in a river or lake, be sure to investigate is below the water surface. Often there are rocks or branched hidden in the water.
When she woke up, she realized that the things she had dreamt about could not ______ have happened.
— We ________ of gas. I’m afraid we can’t go much further. — I know there’s a gas station ahead. Will it last until we get there?
At times, he felt ____ difficult to _______ himself to getting up early.
As we all know, it was ___ that resulted in the terrible car accident.
Although money is important, not many people ______the idea that money brings happiness.