How does 'the system of checks and balances' ensure in a power-sharing?

Power sharing means when power is equally shared among the organs of government and that no one organ of the government tries to control the other.

The system of checks and balance means all the branches of the government keep a tab on each other to ensure proper functioning of the government. Each branch "checks" the power of the other branches to make sure that the power is balanced between them.

The Legislative branch creates law, the Executive branch (the President and Vice President) executes and enforces those laws and the Judicial branch reviews what actions are legal and what actions are illegal. The Judiciary also makes sure that many of the protections afforded individuals in the Constitution are followed.