一生懸命働いて

working hard

→ 一生懸命
phrase Rare #23,047
working hard 一生懸命 means “with all one's effort” or “as hard as possible.” The て-form 働いて connects to what follows, meaning “working hard and...” or, with も, “no matter how hard someone works.”
JA: 一生懸命働いて、家族を支えています。
EN: I work hard to support my family.

ジェーンスミス会社で一生懸命働いています

Jane Smith works hard at the company.

毎日ホテルで一生懸命働いています

I work hard at a hotel every day.

ジョーンズ氏は一生懸命働いて利益を得ることを良いことだと信じている

Mr. Jones believes that working hard and making a profit is a good thing.

彼は一生懸命働いて疲れているようだった

He looked tired from working so hard.

今まで彼らは一生懸命働いてきた

They have worked hard up to now.

いくら一生懸命働いて彼の暮らし少しも良くならなかった

No matter how hard he worked, his life didn't improve in the slightest.