multiply
multiply — verb
1. to calculate the total that results when a number is added to itself a certain n
to calculate the total that results when a number is added to itself a certain number of times — for example, multiplying 4 by 3 gives you 12 because 4 + 4 + 4 = 12.
Folake multiplied 8 by 7 in her head and announced the answer before anyone else.
multiply + number + by + number for arithmetic operation
The maths teacher asked the class to multiply 15 and 6 and write the answer.
multiply + number + and + number (alternative pattern)
If you multiply 10 by 100, the product is always 1,000.
Rohan is learning to multiply two-digit numbers in his maths class this term.
To find the area of a rectangle, multiply the length by the width.
- divide
the inverse math operation
文法句型
multiply + number + by + number
multiply + number + and + number
用法筆記
The pattern 'multiply A by B' uses the preposition 'by', not 'with'. The result of multiplication is called the product.
常見錯誤
2. to grow or cause something to grow a lot in number, amount, or degree, often muc
to grow or cause something to grow a lot in number, amount, or degree, often much more than expected.
The company's profits multiplied five times in three years after the new product launch.
intransitive: amounts or figures multiply (grow rapidly)
Social media posts about the festival multiplied overnight after the video went viral.
New housing developments have multiplied along the coast since the highway opened.
Prolonged exposure to direct sunlight can multiply the risk of skin damage.
Rumours about the merger multiplied after the CEO cancelled the press conference.
- increase
general term for becoming larger; less dramatic
- proliferate
suggests rapid, widespread spread of things like ideas or products
- escalate
implies intensification, often of negative things (conflict, costs)
文法句型
multiply + noun phrase (object)
noun phrase + multiply (intransitive increase)
用法筆記
Often appears with 'by' to state the factor of increase: 'multiply by five'. Common objects include profits, costs, risks, problems, challenges, and effects. Subjects are often abstract — rumours, posts, concerns, opportunities.
常見錯誤
3. of living things — such as animals, bacteria, or cells — to increase in number b
of living things — such as animals, bacteria, or cells — to increase in number by producing young or new individuals.
Rabbits multiply very quickly when food and shelter are both plentiful.
intransitive: animals multiply in suitable conditions
Bacteria can multiply every twenty minutes in a warm container of milk.
micro-organisms multiply in warm, nutrient-rich environments
The fish multiply in the river during the spring season when the water warms up.
Aphids multiply rapidly on rose bushes during hot and humid weather.
文法句型
living thing + multiply (intransitive)
用法筆記
Only used of non-human living organisms — animals, bacteria, cells, plants, insects. For humans, use 'reproduce' or 'have children' instead.
常見錯誤
multiply — adverb
1. involving or affecting several different aspects, levels, or ways at the same ti
involving or affecting several different aspects, levels, or ways at the same time.
The rural community is multiply disadvantaged by poor transport and limited job options.
multiply + adjective describing compounded disadvantage
The company is multiply owned by a group of international investors.
Children from low-income families may be multiply affected by poor housing and limited healthcare.
The new policy was multiply beneficial, cutting costs and improving service at the same time.
- in multiple ways
less formal; phrasal alternative
- on several fronts
idiomatic; suggests activity across different areas
文法句型
multiply + adjective
multiply + past participle
用法筆記
Very formal. Almost always appears before an adjective or past participle (e.g. multiply disadvantaged, multiply owned, multiply affected). Rare in everyday conversation.
常見錯誤
multiply — adjective
1. made of several layers or thicknesses (plies) of material, giving extra strength
made of several layers or thicknesses (plies) of material, giving extra strength or thickness.
Multiply plywood is stronger and more durable than single-layer board for construction work.
multiply + material noun (technical usage)
The upholsterer chose multiply fabric for the sofa because it resists wear better.
Multiply paper is often used for luxury packaging that needs a thick, sturdy feel.
Multiply glass panels provide better sound insulation than standard single-pane windows.
- multi-layer
more common in modern usage
- laminated
suggests layers bonded together under pressure
- single-ply
made of one layer only
文法句型
multiply + material noun
用法筆記
Extremely rare and specialised. Mostly used in technical or trade contexts describing plywood, textiles, paper, or glass. The word 'ply' here refers to a single layer or thickness.