Two roles of Fiscal policy

There are two roles of fiscal policy
The first one is deal with the severe inflation and deflation that means
the government can use Fiscal policy to avoid the economic in the severe
and extended decline.and for deflation Fiscal policy ,
it can avoid the severe inflation.
The second role is to flat the economic fluctuation of the economic cycle.
when the economic get better, the government need increase the tax and make the
government spending down.It can bate the economic expand.