Sri Ramanuja wrote the commentary for the Brahmasutras . It was given acceptance by none other than Goddess Saraswathi Devi Herself. Hence the commentary of Ramanuja a.k.a Bodhayana Vriddhi Grantha came to be known as Sri or Sree Bhashyam.
This Sri Bhashyam commentary is difficult to follow if one does not know Sanskrit .
Hence Sri Vaishnava Sri Krishnamachari has further simplified The Sri Bhashyam commentary in Tamil by giving the meanings for difficult words and terms then and there. Even those who do not know Sanskrit can easily follow these commentaries.