Other ship groundings and occasional oil spills have marred the habitat .
其他船舶搁浅和偶尔漏油事件也对这块栖息地造成破坏。
Although far from commonplace , school shootings have periodically marred america 's educational landscape over the years .
尽管不是普遍发生的事件,校园枪击案近年来时常破坏美国教育界的平静。
But higher education is nevertheless marred by inefficiencies and skewed incentives .
不过,高等教育仍然遭受着低效率和不准确的激励的破坏。
Done correctly , digital broadcasting can make images sharper on even the oldest of analogue sets-with none of the " ghosting " and other electronic noise that marred analogue broadcasting .