To show our respect, we usually take our gloves off _______ we are to shake hands with.

— Do remember to take this medicine three times a day with warm boiled water. — _________.

The teacher told the students that there          a meeting at three o’clock.

I had just settled in the new place and didn’t know ____________________.

Although Fleming discovered Penicillin, it was over a decade ______ someone else turned it into the great drug of the 20th century.