Now more and more people prefer _____ to_____ in order to reduce the air pollution.
—What do you think of the new bridge? —I have never seen _____ before.
. —A new shop ________ for a week nearby. Let's go and have a look. —Great idea. But I'm told it doesn't __________ on Mondays.
“Underground” is the only word in the English language _______ begins and ends with the letters “und”.
People should ______ from ______ down the trees to protect the earth.
—Mr. Li’s never been to Shanghai, has he? — . He went there to attend a meeting last week.