1. She's been slaving away in the kitchen all morning.
她整个上午都在厨房里辛苦地干活。

2. He is slaving away to pay for his university tuition.
他为了支付大学学费而拼命工作。

3. They had been slaving away in the heat all afternoon.
他们在酷热中辛苦地劳作了整个下午。

A: You look exhausted. Have you been working all day?
A：你看起来精疲力竭。你工作了一整天吗？

B: Yes, I've been slaving away at this report since this morning.
B：是的，我从今天早上开始就在埋头苦干这份报告。

1) 拼命工作

2) 没完没了地干活

3) 辛苦劳作

1. 辛苦地工作，没完没了地干活

e.g.
She's been slaving away in the kitchen all day.
她一整天都在厨房里辛苦地干活。

verb phrase

1. to work extremely hard or continuously for a long period of time

Synonym: toil away, grind away