The document outlines the main tasks of engineers doing localization testing: 1) Find and extract words/sentences from documents and systems to input files. This involves analyzing file types like documents, HTML files, and Android strings.xml to find linguistic parts. 2) Analyze databases like Oracle, MySQL, and SQLite to identify tables and columns containing language fields and export them to files. 3) Send input files to translators and receive output files back. 4) Push translated files back to systems, either by replacing old linguistic files/folders or updating database fields and records with new translated values.