27. “I’ve lost one of my gloves.” “You _____ it somewhere.” (A) must drop (B) must have dropped (C) must be dropping (D) must have been dropping

24. By 2050, there will be 9 billion people in the world. They will need water to drink, to grow crops, and _____. Some areas of the world are drying up. A drier planet and more demand mean it is vital to use water wisely. (A) making energy (B) to make energy (C) that makes energy (D) make energy