How is the Executive controlled in the exercise of its powers and functions?

• In a parliamentary system of
  government during “questions time”
  members of the legislature are free to ask questions on any activities of government. This
  provides the legislature opportunity to
  ascertain how government policies are being carried out. 
• The
  legislature in a parliamentary system could pass a “vote of no confidence” on the prime
  ministers and his government. The government has to resign for a
  new election to be  conducted. 
• In
  a presidential system of government, the president could be impeached by the legislature if the
  president violates the constitution.
•  The
  power to approve the annual budget by the parliament is a
  way of controlling the executive. The executive must comply
  with annual budget as approved by the legislature. 
• The
  members of the legislature have the power to set up aprobe on any ministry and investigate any allegation against any ministry.
•  The
  power of approval given to the legislature in respect of nominees for ministerial and other appointments is another way through which the legislature control the executive.
•  In a presidential
  system of government the legislature has the
  power to over ride the veto of the president or executive on laws passed by the legislature. Once the legislature over rides
  the president’s veto, the executive must comply. 
• By
  constant and constructive criticisms by the people in the  pages
  of newspapers, radio, television, the executive tries to live up to expectation.