Derailleur gears by 13 drive-train. Most road bicycles have two chainrings, and touring bicycles commonly have three. The rear derailleur serves double duty: moving the chain between rear sprockets and taking up chain slack caused by moving to a smaller sprocket at the rear or a smaller chainring by the front derailleur. In order to accomplish this second task, it is positioned in the path of the bottom, slack portion of chain. Sometimes the rear-derailleurs are re-purposed as chain tensioners for single-speed bicycles that cannot adjust chain tension by a different method. Although variations exist, as noted below, most rear derailleurs have
Influence of French on English in brackets, then comes its Old French origin in bold and the century of its introduction on the right. Influence of French on English There has been a long-standing influence of French on English, in terms of syntax, grammar, lexicon, spelling and pronunciation. Most French vocabulary that entered English occurred after the Norman conquest of England in 1066 and the establishment of a French-speaking administration. French became the language of the court, the administration and the elites for several centuries, until after the Hundred Years War. English has been constantly influenced by French from that time till present day. According