16. —Who____ it be that is knocking at the door?
—It ____ be Father, but I’m not sure.
| A．can; must | B．can; may | C．must; can | D．may; must |
________ the English speech competition will be a lot of work, so I need some volunteers to help out.
| A．Organize | B．Organized |
| C．Organizing | D．Being organized |
If water becomes increasingly scarce in decades ________， water shortage will become a hot issue all over the world.
| A．coming | B．having come |
| C．to come | D．to be coming |
Misunderstandings ________ from lack of social communication, unless ________ properly, may lead to serious problems.
| A．arisen; handling | B．arising; handled |
| C．rising; handled | D．risen; handling |
________ enough money, Li Hua was unable to buy the new house.
| A．Not saved | B．Not having saved |
| C．Not to save | D．Not saving |
Despite the government's measures to cool the house market, housing demand in China still grew steadily in the second half of 2012，________ a rapid rise in house prices.
| A．resulted in | B．to result in |
| C．resulting in | D．being resulted in |