.I soon found that the work I was doing had already been done by someone else – ________, I was wasting my time

依次填入下列横线处的成语，最恰当的一组是（ ）① 这是南美洲地区最著名的植物园之一，里面的植物品种众多，但与整个亚马逊原森林里的植物相比，不过是 ，不值一提。② 在颁奖典礼上，他公开表示自己的贡献很有限，实在是 ，不配受如此隆重的褒奖，而应该把这个奖颁给他身后的整个团队。③ 虽然人体对某些元素的需要量 ，但如果缺少了它们，人类就会处于亚健康状态，甚至患上各种疾病。

I left my handbag on the train, but luckily someone gave it to a railway official.—How unbelievable to get it back! I mean, someone ______ it.

_ __ __, I have to put it away and focus my attention on study this week.

Making mistakes is a part of life. ________matters is _________ you do afterwards.