as blind as a bat字面意思是“像蝙蝠一样看不见”，常用来表示某人“判断力差、有眼无珠、视觉有困难的”。

【例句】
Without her help, he will act as blind as a bat.
她只要不帮他，他的判断力就会很差。

What's worse. I forgot my glasses and as blind as a bat now.
更糟的是，我忘戴眼镜了，现在什么都看不清。