If you have a translated text but you are not sure of its grammatical corrections, you need a service called "text editing." The translation is proofread by a translation-editor for stylistic, grammatical and other mistakes. An original text, at this point, is not mandatory but it is desirable.
Lingvo Pro performs all sorts of editing and proofreading:
Text editing
Your text is edited by an experienced linguist editor whose task it is to rule out all potential discrepancies, mistakes or inaccurate choice of words.
Rewriting
Rewriting means change of the text by keeping its original meaning. Unlike editing, rewriting focuses on creative revision of the text by completely keeping its original meaning.
Text collation
Text collation is crucial during negotiations when the parties make changes to their part of the documents. When this is the case, the “first” party may not always have full information about all changes and could be willing to find out what exactly the “second” party changed in the documents in its language. Our editors will compare the document versions and will help find changes, if any.
Text editing by a native speaker
In certain cases the text is required to be edited by a native speaker. This enables reviewing the text for contemporaneity, adding national character and identifying figures of speech that are not characteristic for the target country or dialect.