An elder brother, a younger sister, an elder sister.

一个哥哥，一个妹妹，一个姐姐。

youdao

Oh, so you're Peter's younger brother.

噢，这么说你是彼得的弟弟。

《柯林斯英汉双解大词典》

She was accompanied by her younger brother.

她由她的弟弟陪着。

《柯林斯英汉双解大词典》

Bryan was the younger brother of the famous Democrat and populist leader, William Jennings Bryan.

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He believes that a virgin like the Lady is secure or safe from the violent attacks imagined by his younger brother.

他认为像那位女士那样的处女，在他弟弟想象的,暴力袭击中是很安全的。

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Let's say that you're talking to your younger brother and sister.

假设你正在和弟弟妹妹说话。

It's important 课堂 - SpeakingMax英语口语达人

Masaaki Tamenaga's metalworking factory consists of five relatives-father, mother, older brother, younger brother and younger brother's wife.

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But as police handcuffed the older brother, the younger brother barreled toward them in the carjacked SUV.

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And my first brother looked at his younger brother, who was following in his footsteps, with eyes of pity.

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