Meaning: 'City' refers to a large human settlement characterized by significant infrastructure, including buildings, roads, and public services, typically with a high population density.

Wrong options:

• world: The term 'world' is too broad and does not specifically refer to a human-made environment, making it less relevant in this context.
• planet: 'Planet' refers to a celestial body and does not fit the context of human architecture or urban development.
• earth: While 'earth' can refer to the planet, it lacks the specificity of 'city' in relation to modern architecture and urban settings.

Correct answer: vertical

Explanation: The term 'vertical' is the correct choice as it describes the upward direction of transport, which is essential for high-rise buildings. It fits grammatically as an adjective modifying 'transport' and contextually aligns with the need for moving people and goods upwards in a city.

Meaning: 'Vertical' means oriented up and down, which is crucial for describing the type of transport needed in tall buildings.

Wrong options:

• horizontal: 'Horizontal' refers to a side-to-side direction, which contradicts the context of moving upwards in buildings.
• steep: While 'steep' describes a sharp incline, it does not accurately convey the concept of upward transport in a general sense.
• perpendicular: 'Perpendicular' indicates a right angle and does not directly relate to the concept of transport direction.

Correct answer: forms

Explanation: The word 'forms' is appropriate as it refers to different types or categories of power used in lifting devices. It fits grammatically as a plural noun and contextually aligns with the discussion of various methods of lifting throughout history.

Meaning: 'Forms' refers to different types or variations of something, in this case, types of power used for lifting.

Wrong options:

• designs: 'Designs' implies a focus on the blueprint or plan rather than the types of power, making it less relevant in this context.
• models: 'Models' suggests specific examples or representations, which does not fit the broader context of types of power used historically.
• systems: 'Systems' refers to organized methods or structures, which is too broad and does not specifically address the types of power.

Correct answer: force

Explanation: The word 'force' is the correct choice as it denotes the strength or energy used to perform work, which is essential in the context of hoisting devices. It fits grammatically as a noun and contextually aligns with the discussion of power behind lifting mechanisms.

Meaning: 'Force' refers to strength or energy as an attribute of physical action, particularly in lifting or moving objects.

Wrong options:

• strength: While 'strength' is related, it is more about physical capability rather than the driving element behind devices, making it less precise.
• skill: 'Skill' refers to the ability to do something well, which does not fit the context of mechanical power or energy used in lifting.
• ability: 'Ability' is a general term for capability and does not specifically convey the concept of physical power or energy required for hoisting.

Correct answer: improved

Explanation: The word 'improved' is the correct choice as it indicates that Archimedes made enhancements to an existing lifting device. It fits grammatically as a past participle and contextually aligns with the historical development of technology.

Meaning: 'Improved' means made better or enhanced, indicating that Archimedes' device was a better version of previous lifting mechanisms.

Wrong options:

• elevated: 'Elevated' typically describes something raised to a higher position but does not imply enhancement or improvement in design.
• amended: 'Amended' suggests making changes or corrections, which does not accurately reflect the context of enhancing a device's functionality.
• enhanced: While 'enhanced' also means improved, it is less commonly used in this context and does not fit as smoothly as 'improved' in describing technological advancements.