The World Wide Web is ____ computer network that allows ____ computer users to access information for millions of websites via the Internet.
—Alas! I have left my key to the office in my car. —Don't worry. I ________ it for you. Wait a minute.
—Did you enjoy meeting your old schoolmates at the party last week? —Yes, I did. We ________ each other since we graduated from college.
Siberian Tigers ________ and killed at such a speed that they will disappear from the earth in the near future.
To her disappointment, what she had devoted herself to ________ in nothing but failure.
Give me an undisturbed hour and I ________ the work Tom has left unfinished.