2--Does this mean a person is upside down？
 
1--How's that cooking class going?
 
2--Don't get me started. I am in way over my head.
 
1--But...I thought you were good at cooking.
 
2--Not so much. I'm better at baking.
 
1--Baking cakes and pies and cookies and cupcakes.
 
2--To be "in over your head" means you are involved in a situation that is too difficult for you.
 
1--Think of being in water that is deeper than you are tall.
 
2--You are "in" water that is literally over your head.
 
1--That's where this expression comes from.
 
2--You can be "in over your head" if something is too hard for you, or if you do not feel fully prepared to do something.
 
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注解：
 
1.upside down上下颠倒 
2.situation形势
3.literally照字面地 

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译文：

1--这个习语听起来不怎么安全。In Over My Head.
2--这个习语是在讲一个人上下颠倒了么？
1--厨艺课怎么样了？
2--别提了。对于我来说太难了。
1--但是，我以为你很善于厨艺。
2--算不上。我更善于烘焙。
1--烘焙蛋糕，派，饼干还有纸杯蛋糕。
2--“in over your head”是指你深陷于一个你无法应对的情境。
1--设想身处高于你身高的水中。
2--你便淹没于水中，按照字面意思则是“没过你的脑袋”。
1--这就是这个习语的由来。
2--你可以用这个短语形容遇到某些对于你很难的事情，或者是你感到并没有做足充分准备的事情。