(e) Determine one-one shows a robotic arm that is definitely produced up of two sections Arm1 and Arm2 . Arm1 can rotate all around the shoulder joint A, although Arm2 is linked to Arm1 at the elbow joint B, and can rotate around the joint B. summary包括原稿的所有要点（减去所有细节）。因为省略了所有的细节，所以summary比原始文本短得多。例如，一篇五页的文章的summary可以用一两段来概括。 ... http://summary68914.pointblog.net/Everything-about-summary--49356410