My morning ______ includes jogging in the park and reading newspapers over breakfast.
A. drill B. action C. regulation D. routine
Since Tom ______ downloaded a virus into his computer, he can not open the file now.
A. readily B. horribly C. accidentally D. irregularly
At minus 130℃, a living cell can be ______ for a thousand years.
A. spared B. protected C. preserved D. developed
The traditional view is ______ we sleep because our brain is “programmed” to make us do so.
A. when B. why C. whether D. that
______ he referred to in his article was unknown to the general reader.
A. That B. What C. Whether D. Where
Small sailboats can easily turn over in the water ______ they are not managed carefully.
A. though B. before C. until D. if
