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Idiomatic Expressions — English Bac SVT

This theme feeds the Reading and Writing sections of the Bac SVT English paper (coefficient 2), where a precise word field makes an answer stronger. “It's raining cats and dogs” is about neither cats nor dogs: an idiom has a figurative meaning that cannot be worked out from the words in it — a frequent trap for a candidate who translates too literally.

Relu par Équipe Orka · 30 août 2026

Dans le programme du Bac SVT

English has a coefficient of 2 in the Bac Sciences de la Vie et de la Terre (SVT) stream, level with Philosophy and behind Mathematics and Life & Earth Sciences (coefficient 7) and Physics-Chemistry (coefficient 5). It is one of the subjects that tip a result between one honours grade and the next, so it is worth a small, regular slot.

À l'épreuve

Three parts: Reading Comprehension, Language, and Writing (about 180 words). SVT candidates are used to reading documents and pulling out data — the same skill transfers directly to the Reading section: locate the main idea, the supporting details and the writer's stance before answering.

Objectifs d'apprentissage

  • Reuse this vocabulary field in the Bac SVT Reading answers and in the argumentative essay (coefficient 2)
  • Understand that an idiom's meaning is figurative and not deducible from its words
  • Recognise frequent programme idioms: once in a blue moon, break the ice, a piece of cake, under the weather, cost an arm and a leg
  • Paraphrase an idiom in plain English when its meaning is not certain
  • Avoid translating an idiom word for word from Arabic or French

Notions clés

What is an idiom?

A fixed group of words whose overall meaning is figurative and different from the literal sense of its parts. E.g. “to break the ice” = to ease the tension at the start of a conversation, nothing to do with real ice.

Frequent programme idioms

once in a blue moon (very rarely), break the ice (ease initial tension), a piece of cake (very easy), under the weather (slightly unwell), cost an arm and a leg (be very expensive), let the cat out of the bag (reveal a secret).

Paraphrasing an idiom

If you are unsure of an idiom in an exam, replace it with a plain paraphrase: “extremely expensive” for cost an arm and a leg, “very easy” for a piece of cake. A correct paraphrase scores; a wrong literal translation does not.

Erreurs fréquentes

1

Translating an idiom word for word: “il pleut des cordes” → “it's raining ropes” is meaningless in English; the equivalent idiom is “it's raining cats and dogs”.

2

Taking an idiom literally in a reading text: “he was over the moon” means he was delighted, not that he was in space.

3

Overusing idioms in a formal essay: one or two well-placed idioms add colour, but a formal argument is not built on them.

Exemple corrigé

Énoncé

Explain the meaning of the idiom in this sentence and rewrite it in plain English: “The new laptop cost me an arm and a leg.”

Correction

Identify the idiom. “cost an arm and a leg” is a fixed idiom, not a literal statement.
Give the figurative meaning. It means “to be very expensive”.
Rewrite in plain English. “The new laptop was extremely expensive.”

Le cours, puis l'entraînement.

Orka génère des exercices illimités et des examens blancs corrigés sur tout le programme de Anglais du Bac SVT, avec un suivi de ta progression chapitre par chapitre.

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3 exercices pour t'entraîner

Exercice 1

Easy
What does “a piece of cake” mean? (a dessert / something very easy / a small portion)
Voir la correction
something very easy — “The test was a piece of cake” = the test was very easy.

Exercice 2

Medium
Replace the idiom with a plain paraphrase: “I only see my cousins once in a blue moon.”
Voir la correction
“I only see my cousins very rarely.” — once in a blue moon means very rarely.

Exercice 3

Hard
A student writes “I feel under the weather today, so I will not go to space.” Explain the mistake and correct the sentence.
Voir la correction
The student has taken “under the weather” literally. It is an idiom meaning “slightly unwell”. Corrected: “I feel under the weather today, so I will stay at home.”

Va plus loin sur ce chapitre

Questions fréquentes

How many idioms do I need for the Bac?

A working set of ten to fifteen frequent ones is enough. Knowing their meaning matters more for reading; in writing, one or two well-chosen idioms are plenty.

Can I use a French or Arabic idiom translated into English?

No — idioms rarely translate. Either use the established English equivalent or drop the idiom and state the meaning plainly.

How do I handle an unknown idiom in a reading text?

Use the surrounding context: the sentence and paragraph usually make the figurative meaning clear enough to answer the question, even without knowing the idiom.

How do I fit English revision around a heavy SVT programme?

One short weekly session: one chapter at a time (its rule or word list, two examples, one exercise), then write one short paragraph applying it. Build up a ready introduction and conclusion you can adapt. The goal is a mark above your average, which is well within reach for any consistent student.

How do I use this theme in the Bac SVT essay without sounding generic?

Anchor each key term in one concrete, personal example — a place, a person, a situation you know. A specific illustration in accurate English scores better than a long list of terms with no support, on any of the society prompts in the programme.