Was it 80 years before Christopher Columbus crossed the Atlantic ______ Zheng He hadsailed to East Africa? 

—I’ve read another book this week.—Well, maybe _______ is not how much you read but what you read that is important.

It was not until mid-night_______ they reached the camp site.

Can it be in the drawer ________ you put your keys?

It was because of his illness _____ the meeting had to be put off.