After his long journey from Australia. Tom returned home, ____.
From facts,scientists have ________that more energy is being absorbed from the sun,throwing the earth's energy “out of balance”.
A number of students ________the exam so far,but the number of the students who failed ________great.
The traditional ____________to dealing with complex problems is to break them down into smaller,more easily managed problems.
The English test was so easy that most of the students had no ________finishing it in given time.
Many people ________in old days.