Directions: Read the given passage carefully and answer the questions that follow by selecting the most appropriate option.

Helicopters are $\underline{very}$ different from airplanes. They can do three things that airplanes cannot do. First, when airplanes move upward, they must also move forward, but helicopters can move straight up without moving ahead. Second, helicopters can fly backward, which airplanes cannot do. Third, helicopters can use their rotors to $\underline{hover} in the air, which is impossible for airplanes. Helicopters can $\underline{perform}$ actions that airplanes cannot, they are used for different tasks. Since helicopters can take off without moving forward, they do not need a runway for takeoff. They are used in $\underline{congested}$ areas where there is no room for airplanes or in isolated areas, which do not have airports. Because they can hover, they are used on fire-fighting missions to drop water on fires. They are used in logging operations to lift trees out of forests. Helicopters are used as air ambulances to airlift patients out of situations, which are difficult to reach by conventional ambulances. The police use helicopters to follow suspects on the ground or to search for cars on the ground. Of course, helicopters have military uses because of their design and capabilities.

A helicopter can hover while an aeroplane cannot, according to the passage. 'Hover' in the passage means

Question

Directions: Read the given passage carefully and answer the questions that follow by selecting the most appropriate option.

Helicopters are $\underline{very}$ different from airplanes. They can do three things that airplanes cannot do. First, when airplanes move upward, they must also move forward, but helicopters can move straight up without moving ahead. Second, helicopters can fly backward, which airplanes cannot do. Third, helicopters can use their rotors to $\underline{hover} in the air, which is impossible for airplanes. Helicopters can $\underline{perform}$ actions that airplanes cannot, they are used for different tasks. Since helicopters can take off without moving forward, they do not need a runway for takeoff. They are used in $\underline{congested}$ areas where there is no room for airplanes or in isolated areas, which do not have airports. Because they can hover, they are used on fire-fighting missions to drop water on fires. They are used in logging operations to lift trees out of forests. Helicopters are used as air ambulances to airlift patients out of situations, which are difficult to reach by conventional ambulances. The police use helicopters to follow suspects on the ground or to search for cars on the ground. Of course, helicopters have military uses because of their design and capabilities.

A helicopter can hover while an aeroplane cannot, according to the passage. 'Hover' in the passage means

Accepted Answer

Here is a detailed explanation for the question:

**Explanation:**

The question asks for the meaning of 'hover' as used in the passage. Let's analyze the relevant parts of the passage:

The passage states: "Third, helicopters can use their rotors to $\underline{hover} in the air, which is impossible for airplanes." It then further elaborates on the uses of this capability: "Because they can hover, they are used on fire-fighting missions to drop water on fires."

1.  **Justification for Option 2 (Stay at one place in the air):**
    *   The context of 'hover' being used for "fire-fighting missions to drop water on fires" is crucial. To effectively drop water on a specific target (a fire), a helicopter needs to remain stationary over that spot. If it were moving (straight up, backward, or sideways), it would be difficult to accurately target and deliver the water.
    *   The passage lists 'hover' as the *third* distinct ability, separate from "move straight up without moving ahead" (first ability) and "fly backward" (second ability). This implies that 'hover' is a different action than simply moving up or backward.
    *   Therefore, 'staying at one place in the air' perfectly aligns with the functional description and the distinction from other movements mentioned.

2.  **Why Option 1 (Move straight up in the air) is incorrect:**
    *   The passage explicitly states, "First, when airplanes move upward, they must also move forward, but helicopters can move straight up without moving ahead." This is presented as the *first* unique ability of helicopters. Since 'hover' is listed as the *third* unique ability, it cannot mean the same as moving straight up. The passage differentiates these actions.

3.  **Why Option 3 (Go backward in the air) is incorrect:**
    *   The passage clearly states, "Second, helicopters can fly backward, which airplanes cannot do." This is presented as the *second* unique ability. As 'hover' is the *third* unique ability, it is distinct from flying backward.

4.  **Why Option 4 (Fly sideways) is incorrect:**
    *   The passage does not mention "flying sideways" as one of the unique capabilities of helicopters. The three distinct abilities highlighted are moving straight up, flying backward, and hovering. There is no contextual information in the passage to suggest that 'hover' means to fly sideways.

Based on the context provided in the passage, particularly the use of hovering for fire-fighting missions, and the clear distinction between 'hover' and other movements, **Option 2: Stay at one place in the air** is the most appropriate meaning for 'hover'.