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Lesson 42.01B2

Word Formation: Prefixes ré-, dé-, in-/im-, mal-

Word Formation: Prefixes ré-, dé-, in-/im-, mal-

A handful of prefixes systematically reshape a French verb or adjective's meaning — several are close or exact English cognates, which turns an intimidating unfamiliar word into a familiar root plus a predictable twist.

Grammar Comparison

Grammar Comparison

Prefixes as a decoding key — cognate, but not always 1:1

French

dire (to say) → redire (to say again); faire (to do) → refaire (to redo)

English

to say → to say again; to do → to redo

French reuses a small set of prefixes to reshape a base word in predictable ways: ré- means 'again/back' (dire → redire, faire → refaire), dé- reverses or undoes an action (faire → défaire, courager → décourager), in-/im- negates adjectives (capable → incapable, possible → impossible), and mal- means 'badly/poorly' (heureux → malheureux 'unhappy', adroit → maladroit 'clumsy'). English shares two of these almost letter-for-letter — in-/im- and mal- are the same prefixes, spelled the same way, meaning the same thing (incapable, impossible, malfunction, maladroit is even used as a loanword in English). ré- lines up loosely with English 're-' (redo, resay), but dé- is the least reliable match: French défaire is English 'undo' (un-, not 'de-'), while décourager does match English 'discourage' — so treat each prefix as a decoding shortcut to check against the dictionary, not a guaranteed word-for-word swap.

im- vs. in-: a spelling rule English already follows

French

possible → impossible; capable → incapable; patient → impatient; correct → incorrect

English

possible → impossible; capable → incapable; patient → impatient; correct → incorrect

in- becomes im- specifically before b, m, and p (impossible, immortel, impatient) — a pronunciation-driven spelling rule inherited from Latin, and English follows the exact same rule for the exact same reason (impossible, immoral, imbalance, but incorrect, indirect). A near-identical rule governs French's other negative prefix, il-/ir- before l/r (illégal, irrégulier) — and English does this too (illegal, irregular) — so this is one prefix rule you can transfer directly from English rather than memorize from scratch.

Vocabulary

Vocabulary

FrenchPronunciationEnglish
redireruh-DEERto say again
refaireruh-FAIRto redo
défaireday-FAIRto undo
découragerday-koo-rah-ZHAYto discourage
incapablean-kah-PAHBLincapable
impossiblean-po-SEEBLimpossible
impatient(e)an-pah-SYAHNimpatient
malheureux / malheureusemah-luh-RUH / mah-luh-RUHZunhappy
maladroit(e)mah-lah-DRWAHclumsy / awkward
inutileee-noo-TEELuseless