The students encouraged _____ to go on.
---Do you know who invented ________ telephone?---No. But it is really________ most important invention.
—— I’m thinking of tomorrow’s math test. I’m afraid I can’t pass it. ——______. I’m sure you’ll make it.
Many died from the diseases ______by the Europeans.
There is also a fierce debate over the question ______ human cloning experiments should be allowed.
Scientists still wonder whether cloning will help or harm us and where it ____ us.