thankless

adj.

吃力不讨好的；徒劳无功的；不表示感谢的；不受人注意的

1. Giving advice is usually a thankless act.
   进忠告通常是一种不令人感激的行为。
2. I did much for him but what I got was only his thankless complaints.
   我为他做了那么多，但得到的只是他不知感恩的抱怨。
3. She played a thankless role.
   她扮演了一个受累不讨好的角色。
4. They seldom labour their wits on thankless task.
   他们很少为吃力不讨好的工作动脑筋。

SECURITY: THAT MOST THANKLESS OF TASKS
'THANKLESS THANKS': THE EPISTOLARY SOCIAL CONVENTION IN PHILIPPIANS 4:10-20 1
Conservatism in America : the thankless persuasion
The thankless task of playing genetics with mammalian mitochondrial DNA: a 30-year review.
Better Than A Coin Toss? The Thankless Task of Economic Forecasting
A job in itself: the thankless task for young unemployed people looking for work
Beggar, Psychologist, Mediator, Maid: The Thankless Job of a Chairman.
Law Enforcement Officers Wanted: Good People for a Thankless Job. (Notable Speeches)
The Kinnock Reforms in Perspective: Why Reforming the Commission Is a Heroic, but Thankless, Task
The “Very Thankless Task”: Revision of Lunaceps Clay and Meinertzhagen, 1939 (Insecta: Phthiraptera: Ischnocera: Philopteridae), w...