After being dogged by technical delays for years, sir Richard Branson, virgin Galactic's founder, had recently suggested that a Spaceship Two craft would carry its first paying customers as soon as February 2015.
2015年12月六级真题（第二套）阅读 Section C
柯林斯高阶英汉双解学习词典释义
ADJ-GRADED
顽强的;坚持不懈的
If you describe someone's actions as dogged, you mean that they are determined to continue with something even if it becomes difficult or dangerous.
"dogged persistence""dour determination""the most vocal and pertinacious of all the critics""a mind not gifted to discover truth but tenacious to hold it"- T.S.Eliot"men tenacious of opinion"