SAT Basic
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necessary

/ˈnɛsəˌsɛri/
English Definition
adj. needed to be done, achieved, or present; essential
中文释义
必要的
Example Sentence

Accurate measurement of temperature is necessary for determining the rate of a chemical reaction.

准确测量温度对于确定化学反应速率是必要的。

Antonyms
optional unnecessary
Seen in practice — from the Digital SAT question bank

Historian Thomas Reyes agrees that the printing press mattered but argues that widespread literacy programs, which predated the press by decades in some regions, were an equally necessary precondition, since a printed pamphlet is useless to someone who cannot read it.

From a Cross-Text Connections question · Craft and Structure

Historian Ian Farrow agrees that the mechanical clock mattered but argues that the expansion of railway networks, which required synchronized timekeeping across distant towns, was an equally necessary precondition for the widespread adoption of standardized time.

From a Cross-Text Connections question · Craft and Structure

Historian Samuel Okonkwo agrees that coffeehouses mattered but argues that rising literacy rates, which allowed patrons to read and discuss newspapers distributed at those very coffeehouses, were an equally necessary precondition for the debates Ferretti describes.

From a Cross-Text Connections question · Craft and Structure

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Practice — Definition Match

Which choice best defines “necessary”?

  1. A Admired and considered important
  2. B Confident and direct in claiming one's rights or putting forward one's views
  3. C Needed to be done, achieved, or present; essential
  4. D Not achieving the desired outcome
Show answer

C — Needed to be done, achieved, or present; essential. “necessary” means needed to be done, achieved, or present; essential.

Practice — Which Word Fits?

Which word means “needed to be done, achieved, or present; essential”?

  1. A assertive
  2. B necessary
  3. C unsuccessful
  4. D respected
Show answer

B — necessary. “necessary” means needed to be done, achieved, or present; essential.

Common questions about “necessary”

What does “necessary” mean?

necessary — needed to be done, achieved, or present; essential. In Chinese: 必要的.

How do you pronounce “necessary”?

necessary is pronounced /ˈnɛsəˌsɛri/.

How is “necessary” used in a sentence?

Accurate measurement of temperature is necessary for determining the rate of a chemical reaction. (准确测量温度对于确定化学反应速率是必要的。)

What are synonyms for “necessary”?

essential, required, indispensable — all close in meaning to necessary (needed to be done, achieved, or present; essential).

What is the opposite of “necessary”?

optional, unnecessary — each the opposite of necessary (needed to be done, achieved, or present; essential).

Is “necessary” an SAT vocabulary word?

Yes. necessary is on the SAT Prep Basic list — the everyday academic words the SAT assumes you already have. The Digital SAT does not test vocabulary in isolation; words like this one are tested through Words in Context questions, where you choose the word that completes a passage most logically and precisely.

Progress / 学习进度
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This level: 0 mastered (0% of the level)
The Digital SAT tests vocabulary through Words in Context questions, never as a standalone definition. Learn the word, then use it against a real passage.