______ its size with that of the whole earth, we find the highest mountain does not seem high at all.
____ Helen’s knowledge and vocabulary expanded, she asked more and more questions.
I didn’t know I was spelling a word or even ____ words existed.
In a way, Pompeii is like a time capsule ____ a frozen moment in history.
By the time some scientists ____ the lost towns, they ____ an awesome historical site.
He constantly gets into awkward and absurd situations, ____ audience can be greatly amused.