能否举例分析，请具体说明
追答helpless
Parents often feel helpless, knowing that all the cuddles in the world won't stop the tears...
父母经常感到无能为力，因为他们知道无论多少次拥抱也无法止住眼泪。
Children are dying, and I am helpless to do anything...
孩子们已奄奄一息，而我却无力做任何事情。
Once aboard we were soon helpless with laughter at the absurdity of it...
一上飞机我们就按捺不住，大笑起这事的荒唐。
useless
He realised that their money was useless in this country...
他意识到他们国家的货币在这个国家一文不值。
Computers would be useless without software writers.
没有编软件的人，计算机就会毫无价值。
“一个是指全局的，一个有意向的指。”什么意思？请结合例句说明。