Professor Jordon is well known for his __________ into the habits of the common housefly.
| A．examination | B．introduction |
| C．research | D．expression |
Dan Brown，_____ author of The Da Vinci Code，is _____ very famous American writer．
| A．a; the | B．the; the |
| C．the; a | D．a; a |
Jack，it’s too hot here．______ I open the window？
| A．Shall | B．Will | C．Should | D．Would |
_____ he promised that he wouldn’t be late，he didn’t arrive until the end of the party．
| A．Since | B．Although |
| C．Because | D．Until |
Since the new speed limits ______，the number of accidents in the area has fallen strikingly．
| A．were introduced | B．introduced |
| C．have been introduced | D．have introduced |
When Kerry and Sam met again two years later，each was pleased to see ____．
| A．the other | B．others |
| C．another | D．other |