Derailleur gears operates the lever while pedalling, the change in cable tension moves the chain-guide from side to side, "derailing" the chain onto different sprockets. For more information about the choice of particular gear ratios and sprocket sizes, see Bicycle gearing. "Derailleur" is a French word, spelled "dérailleur" in French, derived from the derailment of a train from its tracks. Its first recorded use was 1930. At least one notable bicycle industry author has attempted to promote the anglicized spelling of "derailer". As of 2013, however, neither Merriam-Webster nor the Oxford English Dictionary has an entry for "derailer". Various derailleur systems were
French articles and determiners French indefinite article is analogous to the English indefinite article "a/an". Like "a/an", the French indefinite article is used with a noun referring to a non-specific item, or to a specific item when the speaker and audience do not both know what the item is; so, « J'ai cassé une chaise rouge » ("I broke a red chair"). Unlike "a/an", the French indefinite article has a plural form, often translated as "some" but usually simply omitted in English; so, « Il y a des livres là-bas » ("There are some books over there" or "There are books over there"). The