The employee ____________ to impress the company with his cleverness and promptness.[ ]

(2013·咸阳二模)We should keep in mind that the earth is our only home and only by saving the environment________ourselves.

Why are you worried — I’m expecting a call from my daughter. She _______ abroad for three days.

Can I use your bike —- Sorry, I don’t have_____.

Everyone in our class was working hard anddoing what we could ________ a good university.