Meaning: 'Planning' means to think about and organize the steps needed to achieve a goal or outcome.

Wrong options:

• envisaging: 'Envisaging' means imagining or visualizing something in the future, which does not fit the context of a lack of intention.
• aiming: 'Aiming' implies directing efforts towards a specific goal, which contradicts the negative construction of the sentence.
• devising: 'Devising' means creating or inventing something, which does not align with the context of having no intention.

Correct answer: suck

Explanation: The verb 'suck' is the correct choice as it indicates the action Booth suggested for the machine, contrasting with the initial function of blowing air. This fits contextually with the idea of cleaning by removing dust.

Meaning: 'Suck' means to draw in or remove something, in this case, dust from the carpet.

Wrong options:

• gasp: 'Gasp' refers to a sudden intake of breath, which is unrelated to the function of a cleaning machine.
• puff: 'Puff' suggests blowing out air, which is the opposite of what Booth recommended.
• gulp: 'Gulp' typically refers to swallowing, which does not apply to the context of a cleaning machine.

Correct answer: remarked

Explanation: The word 'remarked' is appropriate as it indicates a spoken comment made by the inventor. It fits grammatically and contextually, suggesting a casual observation rather than a formal statement.

Meaning: 'Remarked' means to say something as a comment or observation.

Wrong options:

• expressed: 'Expressed' implies a more emotional or formal communication, which does not fit the casual context of the inventor's response.
• voiced: 'Voiced' suggests articulating a thought or opinion, which is less fitting than 'remarked' in this context.
• uttered: 'Uttered' implies a more deliberate or formal speech, which does not align with the informal nature of the conversation.

Correct answer: Mulling

Explanation: The word 'Mulling' fits well as it indicates deep thought or consideration about the problem. It aligns with the context of Booth reflecting on the inventor's response.

Meaning: 'Mulling' means to think carefully about something over a period of time.

Wrong options:

• Reflecting: 'Reflecting' is similar but suggests a more passive consideration, which does not convey the active thought process implied by 'mulling.'
• Contemplating: 'Contemplating' implies a more serious or philosophical consideration, which may not fit the casual context of Booth's thoughts.
• Dwelling: 'Dwelling' suggests lingering on a thought, which does not capture the proactive nature of Booth's thought process.

Correct answer: choked

Explanation: The word 'choked' is the correct choice as it indicates a physical reaction to inhaling dust, fitting the context of Booth's experience. It aligns grammatically and contextually with the action described.

Meaning: 'Choked' means to have difficulty breathing due to obstruction, in this case, from dust.

Wrong options:

• strangled: 'Strangled' implies a more violent or forceful action, which does not accurately describe Booth's experience with dust.
• blocked: 'Blocked' suggests an obstruction but lacks the active, physical reaction implied by 'choked.'
• variety: 'Variety' is unrelated to the context, as it refers to different types or kinds, not a physical reaction.

Correct answer: variety

Explanation: The word 'variety' is appropriate as it indicates a type or category of vacuum cleaner. It fits grammatically and contextually, suggesting that Booth's invention was distinct from others.

Meaning: 'Variety' means a range of different things or types.

Wrong options:

• class: 'Class' refers to a group of items with shared characteristics but does not convey the diversity implied by 'variety.'
• category: 'Category' is similar but lacks the nuance of different types that 'variety' provides.
• nature: 'Nature' refers to the inherent qualities of something, which does not fit the context of describing a type of vacuum cleaner.