e disease will produce a powder poison that will kill the patient.

I didn’t go to Tom’s birthday party yesterday. What about you—________, because I was preparing for the exam all the time.

Did you remember the days ________ we studied in the university?—Certainly.Especially the hard times ________ we spent together.

Science fiction writers often write about _______will happen in “tomorrow’s world”

Tom usually reads English 6:00 every morning.