This is the 7916th most frequent Japanese word.
執拗
Persistent; tenacious; relentless.
Here, '執拗' describes the quality of the questions as being persistent or overly inquisitive.
彼の執拗な質問に困っています。
I am troubled by his persistent questions.
In this context, '執拗' highlights her relentless or determined pursuit of success.
彼女は執拗に成功を追い求めた。
She persistently sought success.
'執拗' in this sentence refers to the dedicated and continual manner in which the teacher guided the students.