He's a hardheaded old man.
他总是好高骛远。
He's aiming too high.
详解：aim high“奢望”、“逞能、逞强”。
He's overreaching himself.
He's out of his league.
他从不认输。
That man never admits defeat.
He never admits he is wrong.
He is a sore loser.
He hates being defeated.
他讨厌失败。
He can't handle defeat.
他是个输不起的人。
他是个难以捉摸的人。
He's very vague.
详解：vague“不可捉摸”、“不清楚的”、“不明确的”。
He's very vague.
他是个难以捉摸的人。
He's just like my brother.
和我弟弟一样。

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