執拗

Kare wa hannin no tegakari o motomete, shitsuyō na sōsa o tzuketa.

He continued his relentless investigation, searching for clues about the criminal.

Aite no jakuten o shitsuyō ni semeru koto de, tsuini shōri o osameta.

By persistently attacking the opponent's weakness, they finally secured a victory.

Kisha kara no shitsuyō na shitsumon ni taishi, shushō wa shūshi reisei ni kotaeta.

In response to the persistent questioning from reporters, the Prime Minister answered calmly from start to finish.

Sono kenkyūsha wa, shinjitsu o kyūmei suru tame ni shitsuyō na made ni jikken o kurikaeshita.

The researcher repeated the experiments to a persistent degree in order to investigate the truth.

Meiwaku mēru ga shitsuyō ni okurarete kuru tame, adoresu o henkō sezaru o enakatta.

Because spam emails were being persistently sent to me, I had no choice but to change my address.

Kanojo no shitsuyō na settoku ni makete, watashi wa tsuini sono keikaku e no sanka o shōdaku shita.

Yielding to her persistent persuasion, I finally agreed to participate in the project.