题目

Eye Health CareDailyHealthy habits mean healthy eyes. Here are some daily tips for eye health.◆P Clean your eyes with pure cold water regularly. This is one of the best ways to keep eyes healthy and disease free.◆Avoid looking directly at the sun◆Roll your eyes up and down, then side to side. Then move your eyes in a circular motion（圆周运动） Exercise5tol0 times a day to relax your eyes◆ Keep a good distance from the computer screen-sit about 22-28 inches away from it.◆Visit your eye doctor on a regular basisThere are also some tips for healthy contact lens（隐形眼镜）w若a外一条直线a与平面a内的一条直线b不平行，则（）A.a与b相交或异面B.a与b一定是异面直线C.a内一定有直线与a平行D.a内一定没有直线与a平行