Derailleur gears a detent or ratchet mechanism which stops the gear lever, and hence the cable and the derailleur, after moving a specific distance with each press or pull. Indexed shifters require re-calibration when cables stretch and parts get damaged or swapped. On racing bicycles, 10-gear rear cassettes appeared in 2000, and 11-gear cassettes appeared in 2009. Most current mountain bicycles have either. Many modern, high-end mountain bikes have begun using entirely one chain ring drivetrains, with the industry constantly pushing the number of rear cogs up and up, as shown by SRAM's Eagle groupsets (1 by 12) and Rotor's recent 1
Interrogative word Interrogative word An interrogative word or question word is a function word used to ask a question, such as "what", "when", "where", "who", "whom", "why", and "how". They are sometimes called wh-words, because in English most of them start with "wh-" (compare Five Ws). They may be used in both direct questions ("Where is he going?") and in indirect questions ("I wonder where he is going"). In English and various other languages the same forms are also used as relative pronouns in certain relative clauses ("The country where he was born") and certain adverb clauses ("I go where he goes").