The process of checks and balances means that each of the three branches of government i.e. legislature, executive and judiciary, are erected such that no branch can assume too much power, which can pose threats to the functioning and jurisdiction of other branches. To explain this, you can adopt the following way

Let's say you want to talk about checks and balances on Legislature. First mention what functions are performed by legislature. Then mention how each of these functions is checked by executive and judiciary.

For example, Legislature can pass any bill with two-third majority in both houses. Now how is this particular function of legislature checked by executive and judiciary?

Check of the executive:

President can veto any ball passed by the legislature

Check of the judiciary

Judiciary can declare the bill unconstitutional after judicial review. Moreover, the power of interpretation of bill rests with judiciary

So in this way, you can analyse the checks and balances on each function and the answer can amount to many pages

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"And how can man die better than facing fearful odds, for the ashes of his fathers, and the temples of his Gods?"