Examples of using It is a source in English and their translations into Bulgarian
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                        Colloquial
                    
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                        Official
                    
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                        Medicine
                    
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                        Ecclesiastic
                    
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                        Ecclesiastic
                    
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                        Computer
                    
It is a source of choline and has brain-stimulating effects.
It is a source of powerful antioxidants,
It is a source of spiritual strength.
It is a source of life that represents(re) birth.
It is a source of serotonin which helps to promote better sleep.
And for others, it is a source of income.
It is a source of folic acid,
In addition, it is a source of proteins, important vitamins and trace elements.
It is a source of spiritual power.
This grain and it is a source of complete protein.
It is a source of happiness.
It is a source of many beneficial substances.
It is a source of much stress.
It is a source of energy and building material for cells.
It is a source of essential fatty acids,
And most importantly- pets, it is a source of smiles and positive….
In addition, it is a source of valuable nutrient that is  easily digested.
For others, it is a source of income.
It is a source of probiotics, that result from the process of fermentation involved in its preparation.
It is a source of basic knowledge.