Complex sentence: On 4 January 2009, India's Ministry of Defence signed a US $2.1 billion agreement with Boeing for the supply of eight P-8Is to replace the Indian Navy's aging Tupolev Tu-142M maritime surveillance turboprops.
Split into simpler sentences: On 4 January 2009, India's Ministry of Defence signed an agreement with Boeing for the supply of eight P-8Is at a total cost of US $2.1 billion. These aircraft would replace Indian Navy's aging Tupolev Tu-142M maritime surveillance turboprops.