In the global economy, a new drug for cancer, _________ it is discovered, will create many economic possibilities around the world.
| A．whatever | B．whoever | C．wherever | D．whichever |
Hotels fill up fast during the busy tourist season, __________it is necessary for tourists to make reservations in advance.
| A．or | B．so | C．for | D．but |
An advantage of being the youngest child in his family is __________he gets a lot of attention.
| A．that | B．whether | C．why | D．when |
His study was a mess with lots of books and magazines __________up everywhere.
| A．to pile | B．having piled |
| C．piled | D．to be piled |
--Oh, I __________my passport!
--Don’t worry. We have time to go back home and get it.
| A．forget | B．forgot |
| C．will forget | D．had forgot |
While looking for some personal documents, I happened to see an album __________some old photographs.
| A．contained | B．to contain |
| C．containing | D．being contained |