This is the 15023rd most frequent Russian word.
подчеркивал
"Подчеркивал" means "emphasized" or "underlined."
In this sentence, 'подчеркивал' indicates that he repeatedly emphasized or pointed out the importance of diligence, stressing its significance in communication.
Он подчеркивал важность трудолюбия.
He emphasized the importance of diligence.
Here, 'подчеркивал' refers to the act of drawing attention to and making distinct the key points of the problem in a speech or presentation.
Докладчик подчеркивал основные аспекты проблемы.
The speaker highlighted the main aspects of the issue.
This usage of 'подчеркивал' describes the literal action of physical underlining of words using a writing tool, indicating emphasis in a written format.