千丝万缕

qiān sī wàn lǚ

countless ties

Character by character

千qiān
thousand

丝sī
threads

万wàn
ten-thousand

缕lǚ
strands

这两家公司有着千丝万缕的联系。

The two companies are tied together in countless ways.

Tone: neutral.

Almost always 千丝万缕的联系／关系.

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