adv. 徒劳的
... 不感谢 = thankless 不感谢 = thanklessly 不感谢 = unthankful ...
thankless 不感谢的；忘恩的；不领情的
We're talking, of course, about the company's line of PackBot robots, who thanklessly perform reconnaissance in hostile areas and disarm explosives so humans don't have to -- sadly, not always making it out in one piece.