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》

His younger brother is not much of a companion for him.

他的弟弟和他志趣不太相投。

《牛津词典》

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

In 1966, Robert and his younger brother Peter literally came to blows at a family picnic.

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Authorities say Tamerlan Tsarnaev and his younger brother, Dzhokhar, also killed a police officer.

CNN: FBI did its job in Tsarnaev probe, Obama says

His younger brother, Dzhokhar Tsarnaev, 19, was captured and charged in connection with the attack.

BBC: Boston bombing suspects' mother regrets emigration to US