He told me his story in private，__________ nobody else knew what had happened to him．
| A．but | B．so | C．while | D．or |
Not until the train pulled into the next station _______ her suitcase gone.
| A．Mary had found | B．had Mary found |
| C．did Mary find | D．Mary found |
____ no cash for food, he broke into an old woman's house, hoping to steal some money.
| A．Because | B．As | C．Since | D．With |
The Internet and the effect______ brought about did a lot of good to our daily life and work.
| A．that | B．what | C．which | D．it |
______ Flying Luxury Hotel of Tomorrow is ______ huge 400-ton aircraft without wings.
| A．/, a | B．The, a | C．The, the | D．A, a |
If we go on using energy so wastefully, __________ are that our oil wells will be dried up before new energy sources can be found to replace oil.
| A．chances | B．opportunities | C．questions | D．problems |