Original sentence: Only the first of these submarines to be constructed, the Dmitry Donskoi, is still in active service with the Russian Navy, serving as a test platform for the Bulava (SS-NX-30) missile which is currently under development.The Typhoons are slated to be replaced with the Borei class starting in 2009
Edited sentence: Only the first of these submarines to be constructed, the Dmitriy Donskoy, is still in active service with the Russian Navy, serving as a test platform for the Bulava (SS-NX-30) missile which is currently under development.The Typhoons are slated to be replaced by the Borey class starting in 2009