彼は自分の研究に時間を惜しまなかった。の英語

He didn't spare time on his studies.

He didn't spare any effort on his studies.

He grudges to give out information on his research.

He spends very little time on his studies.

He became less and less interested in his studies.

No wonder he didn't feel like studying.

He didn't study at all.

He looked upon any time not spent in study as so much lost time.

He has failed in the examination owing to his idleness―in consequence of his idleness.

He works as hard as any one

He is second to none in diligence.

He is absorbed in his studies.

He doesn't study as hard as he used to.

He is master of his own time.

Hardworking as he was, sometimes he felt disinclined to study.

He is absorbed in his studies―engrossed in his studies.

He has ceased to work hard as he used to.

He regrets having neglected his studies in his school days.

He regret having neglected his studies in his school days.

He makes up by diligence for his want of ability.

He is wanting in ability, but he works hard.

He's as hardworking as any.

He does not work hard at the best of times.

He has hardly studied this term.

He is as diligent a man as ever lived.

He repents of his past idleness.

He worked while the others were playing.

He does not work hard at the best of times.

He always studies hard.

He worked very hard, but could make little progress.