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
Word sort have a responsibility to students they serve to identify their needs and implement instructional strategies to scaffold students’ understandings of sounds. Intervention strategies may be necessary in remediating students who cannot correctly identify sounds in isolation on a given opportunity. Programs like Reading Recovery have contemporary phonemic techniques embedded in the program. Also, books and poems may specifically focus on word families and similar sound patterns for children to identify and understand in context. Sound sorts can be integrated through programs, or very inexpensively through teacher-created materials. For example, students can sort pictures by beginning sound, rhyme, or ending sound.