大跌眼镜 (dàdiē yǎnjìng) the glasses fell off in surprise

Usage:

据说，人们还没有利用耳朵挂住眼镜之前，只是用手扶住镜片。后来为了腾出一双手而利用脸部肌肉夹住眼镜。可是，当人们遇到惊讶的事情而瞪大眼睛的时候，眼镜就掉了下来。“大跌眼镜”是指对出乎意料的结果或不可思议的事物感到非常惊讶。
As the story goes, before people used eyeglasses that hooked around their ears, they held their glasses with their hands. Later, people started to use their facial muscles to clamp their glasses in order to use their hands to do other things. However, their glasses would fall off when people surprised them to the point of opening their eyese too wide. “大跌眼镜” means that someone feels surprise when encountering an unexpected result or unbelievable thing.

Sentences:

1、Tā shūdiào le bǐsài, zhēnshì ràng rén dàdiē yǎnjìng.
他输掉了比赛，真是让人大跌眼镜。
It really surprised people that he lost the game.

2、Ràng quánjiā dàdiē yǎnjìng de shì tā tōule chāoshì de shāngpǐn.
让全家大跌眼镜的是他偷了超市的商品。
What really shocked every family member was that he stole goods from the supermarket.

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