meaning of three idoms

1)get a big head
Meaning: arrogant; overly confident.
e.g. He is big headed; He has got a big head ever since he won that competition; After all those winnings, his head got too big, and now he thinks he can win anything.

2)get his head in the cloud
meaning: has unrealistic ideas
e.g. Peter has his head in the clouds; he has detailed plans about travelling around the world, when he can barely afford to pay his rent.

3)go to his head
meaning: let something bother him
e.g. "Everybody makes mistakes; don't let this one go to your head; just move on !"

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