He died, literally , at the chalkboard at age 83.他过世了, 83岁的时候, 在黑板前.Then one morning we were working math problems at the chalkboard.后来有一天早晨,我和玛丽在黑板上写下了数字题目.The map was drawn on chalkboard with ink - markers.那张地图用记号笔画在一块...
A larger number of budlike protuberances form and are pinched off to give microcells.大量芽状突出物形成,并被脱出以获得微细胞.The diseased trees are marked by protuberances on their bark.有病的树木可由其树皮上的结节看出.One of the natural protuberances on ...