. —Who____ it be that is knocking at the door? —It ____ be Father, but I’m not sure.
Forests ________ and burned at such a speed that they will disappear from the earth in the future.
—I’ve got a cough and my chest hurts. —________.Let me examine you.
What I need is ________ book that contains ________ ABC of oil painting.
Sam insisted that he________ the law and________.
—________ when has the country been open to international trade? —1978,I suppose.