My friend was down with the flu, and ________ couldn’t come to the party.
| A．instead | B．however |
| C．therefore | D．otherwise |
our earth, or else it will be no longer fit for us to live on.
| A．Protect | B．To protect | C．Protecting | D．Protected |
Professor Williams keeps telling his students that the future to the well- educated.
| A．belongs | B．is belonged | C．is belonging | D．will be belonged |
Trees on the hills can stop the rains from away the soil.
| A．to wash | B．washed | C．washing | D．washes |
What is the best way you can imagine the overuse of water in our daily life.
| A．to reduce | B．reducing | C．reduced | D．reduce |
The boy be very naughty, but he is very lovely.
| A．might | B．can | C．may | D．need |