translation.en: Yarn bombing is when you take knitted or crocheted material out into the urban environment, graffiti-style -- or, more specifically, without permission and unsanctioned.
translation.zh: 毛线轰炸指的是 当你将针织或钩编所用的材料 以涂鸦艺术用于城市环境中 然而，准确的说 这种行为并未得到允许和批准。