It often happens that you do not know the origin of the stain.
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Before trying to remove such stains, you need to examine the type of fabric they are on and make sure if you can clean it with water or only chemically. If the fabric is suitable for washing with water, you can start with applying cold water on the stain. For most materials (except cotton and linen), you can rub a cotton stub soaked with vinegar against the material. Unless it is wool or silk, you can be take advantage of ammonia for cleaning. White fabrics can be bleached with a bleacher. Most fabrics can be cleaned with alcohol. When you choose the method of stain removal, firstly start with a less visible part of the material. This prevents discoloration.
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