State briefly the position of the Prime Minister in the Parliamentary system of the nation.

The Prime Minister is the DE FACTO or real head of the government, while the President is only the nominal head. (1) He is the LEADER OF THE LOK SABHA and the chief spokesman of the Government, defending its policies and intervening in controversial issues; he addresses the nation on important occasions and during emergencies. (2) He is the LINK between the President and the Council of Ministers, and all the authority formally vested in the President is in practice exercised on his advice. (3) He REPRESENTS INDIA abroad, decides the country’s relations with other nations, and is Chairman of the NITI Aayog and of the Atomic Energy Commission.

Three marks, so three distinct aspects of the position — leader of the House, link with the President, and national and international representative. Open with the phrase DE FACTO HEAD, contrasted with the President’s nominal headship; that single sentence frames the whole answer. The quotable descriptions are "the keystone of the Cabinet arch" and "primus inter pares" — first among equals.