八竿子（也）打不着。(Bā gānzi (yě) dǎ bù zháo.)It is far away. / They are unrelated at all.

Explanation

“八竿子（也）打不着”这句俗语，虽然出处不统一，但本义都是指距离很远。比喻两者之间关系很远或者根本没有关系。
Though the derivations of this slang are different, its original meaning is far distance. It metaphorically means the relation between two persons or things is not close or they are unrelated at all.

Words:

表姐biáojiě:cousin;

亲戚qīnqi:relative.

Sentences

1、Jiǎ: Nǐ yuǎnfángbiǎojiě zhǎo nǐ shénme shì?
甲：你远房表姐找你什么事？
A: What does your distant related cousin ask you to do?

Yǐ: Bā gānzi yě dǎ bù zháo de qīnqī, yào zhǎo rén bāngmáng shí, xiǎngqǐ wǒ le.
乙：八竿子也打不着的亲戚，要找人帮忙时，想起我了。
B: We are relatives not close. She remembers me when she needs help.

2、Jiǎ: Wǒ méiyǒu bèi lùyòng, shì yīnwèi Yīngyǔ bù hǎo.
甲：我没有被录用，是因为英语不好。
A: I haven’t been employed because of my bad English.

Yǐ: Wèi shénme? Nà fèn gōngzuò gēn Yīngyǔ bā gānzi dǎ bù zháo a.
为什么？那份工作跟英语八竿子打不着啊。
B: Why? That job has nothing to do with English.

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