fail to see/understand

fail to see的字面义为“失败于理解”，这是说主体自己不明白，这么曲里拐弯地从自己慧力不够来表达，就是装一下formal而已， 如

【例句 1】I fail to see why you find it so amusing. （我不明白你为什么觉得它这么有趣。）[朗文当代英语词典]

【例句2】I fail to see why you can't work on a Saturday. (我不明白你为什么不能在星期六工作。)[剑桥高级学者辞典]

【例句3】I fail to see the appeal of these highly expensive products. (我看不出这些昂贵产品的吸引力。) [剑桥高级学者辞典]

【例句4】I fail to see why it's necessary to cut down these beautiful trees. (我不明白有啥必要去砍伐这些美丽的树木。) [剑桥高级学者辞典]

【例句5】I fail to see (= I don't understand) why you won't even give it a try. (我不明白你为什么不试试。)[牛津高级学者辞典]

【例句6】That's how it was in my day and I fail to see why it should be different now. (这就是我那个时代的情况，我不明白为什么现在会有所不同。)[柯林斯高级学者辞典]

see自然也可以换作understand, 如

【例句7】What I fail to understand is why her actions upset you so much. (我不明白的是，为什么她的行为让你如此难过。) [剑桥高级学者辞典]

【例句8】The matter seems quite simple to me and I fail to understand why it is proving so hard to resolve. (这件事对我来说似乎很简单，我不明白为什么它很难解决。)[剑桥高级学者辞典]

上述说话的基调是：说话人不太认同，或者觉得对方有点烦。