______ there is no water left on the earth —I really don’t know.

The story is and all of us are in it.

He usually goes to work ______ his bike, but today he goes ______ foot.

Students are not required to take the TOEEL or the IELTS test but we welcome the submission of your score if you have taken _____.

The company is deep in _____, so you’d better avoid dealing with it.