quantity

quantity — 名詞

1. The total size or count of something that can be weighed, measured, or expressed

1.名詞A2
釋義

數量；量

可測量或計算的數目或份量

The total size or count of something that can be weighed, measured, or expressed as a number — for instance, the volume of water in a swimming pool or the number of seats in a theatre.

例句

The recipe calls for a small quantity of salt, about half a teaspoon.

食譜需要少量的鹽，大約半茶匙。

adjective + quantity of + uncountable noun

Jessica checks the quantity of milk left in the carton each morning before school.

Jessica 每天早上上學前都會檢查牛奶盒裡還剩下多少牛奶。

quantity of + noun for checking amount

同義詞
  • amount

    more common in everyday speech; used especially for uncountable things (amount of water, amount of time)

  • volume

    specifically for three-dimensional space or the amount of sound; more technical than quantity

  • number

    used only with countable items (number of people, number of chairs); not interchangeable with quantity for uncountable nouns

文法句型

quantity of + noun

quantities of + noun

adjective + quantity of + noun

用法筆記

Quantity is the most general word for 'how much' or 'how many'. It is often contrasted with quality, which describes how good something is rather than how much of it exists. In everyday speech, 'amount' is more common for uncountable nouns and 'number' for countable nouns; 'quantity' sounds slightly more formal.

常見錯誤

❌I need a big quantity of apples for the party.
✅I need a large number of apples for the party.
💡For countable items, 'a large number of' or 'many' sounds more natural than 'a large quantity of' in everyday conversation.

2. a large or more-than-enough amount of something — used when the size or number i

2.名詞B1
釋義

大量

數量龐大或超出所需的份量

a large or more-than-enough amount of something — used when the size or number is important or impressive, such as a quantity of rice stored in a warehouse or a quantity of steel needed for a building project.

例句

The warehouse contains a quantity of rice that feeds a whole region for a month.

這座倉庫儲存的大米足以供應整個地區一個月。

a quantity of + noun (large amount in storage)

Arjun ordered a quantity of steel beams for the new bridge across the river.

Arjun 為河上新橋的建設訂購了一大批鋼樑。

ordered a quantity of + noun (construction context)

同義詞
  • abundance

    more emphatic and positive; suggests more than enough (an abundance of food)

  • mass

    suggests a solid, undivided bulk; used for physical substances (a mass of papers)

  • bulk

    focuses on size or volume rather than number (the bulk of the shipment)

文法句型

a quantity of + noun (singular/uncountable)

quantities of + noun

用法筆記

In this sense, 'a quantity of' often implies a notably large amount, but the exact size depends on context — a 'quantity of medicine' might be just a few bottles while a 'quantity of grain' could be many tonnes. The phrase 'in quantity' (without 'a' or 'of') means 'in large amounts' and comes before a verb or at the end of a clause.

常見錯誤

❌The company bought quantity of wood.
✅The company bought a quantity of wood.
💡When used to mean 'a large amount', the indefinite article 'a' is required before 'quantity of'.

3. a value or amount that can be expressed as a number in a mathematical equation o

3.名詞B2
釋義

量（數學）

數學或科學中可用數值表示的測量值

a value or amount that can be expressed as a number in a mathematical equation or scientific calculation — for example, the speed of light, the temperature of a liquid, or the variable x in an algebraic formula.

例句

The students learned to solve for the unknown quantity x in the algebraic equation.

學生們學習求解代數方程中未知的量 x。

unknown quantity (math term for a variable)

In E = mc², each letter stands for a physical quantity like energy or mass.

在 E = mc² 這個方程式中，每個字母代表一個物理量，例如能量或質量。

physical quantity (science term)

同義詞
  • value

    more common in everyday maths (the value of x); narrower than quantity, which includes the concept of measurability

  • magnitude

    more technical; emphasises size or scale rather than count (magnitude of an earthquake)

  • measure

    focuses on the process or result of measuring (a measure of distance)

文法句型

a/the + adjective + quantity

physical/mathematical/unknown + quantity

用法筆記

In mathematics and science, 'quantity' refers specifically to a measurable property that can be assigned a number and a unit. Unlike sense 1, this sense is always technical and precise. Common compound terms include 'physical quantity', 'vector quantity', 'scalar quantity', and 'unknown quantity'.

常見錯誤

❌In math class, we learned about quantity x.
✅In math class, we learned about the quantity x.
💡In the mathematical sense, 'quantity' nearly always takes a determiner (the, a, this) before it.