Many people agree that knowledge of English is a must in international trade today.
Due to the volcano eruptions in the Republic of Iceland, all the flights are delayed or cancelled, so the conference has to be ________.
The news spread quickly through the village ________ the war had ended, ________ made villagers wild with joy.
After we compare the two, we find this design is ________ that one.
More forests are being destroyed. As a result, a lot of good earth ________ each year.
—Look! Isn’t that Peter’s sister?—No, it ________ be her—I’m sure she doesn’t wear glasses.