Medium-grained rocks can be composed of quartz grains, feldspar grains (arkose), or rock fragments and clay (graywacke). Sandstone (Photograph by Parvinder Sethi). Medium-sized grains in clastic sedimentary rocks form sandstone. This sample is a quartz sandstone.
Bliss â¢ McCabe: Discourse Genres 135 special interests and can give lengthy descriptions ofrelevant objects such as rocks or music).â¢ We have identified the following components thatappear to be necessary for a complete proceduraldiscourse regarding how a game is played: goals,players, materials, and procedures.
1 A discourse or literary style in which the narrator recounts his or her own experiences or impressions using such forms: an essay written in the third person. 2  A perspective in a video or computer game in which the screen depicts a point of view other than that of the player's avatar.