一个宏观经济学的问题 要用英文回答的 describe how govenment expenditure might be used to smooth out fluctuations in the level of economic activity.

there are two instances
in one hand,when the economy is in the state of overheating,the govenment may tax more or reduce expenditure to maintain economic stability.when the govenment reduce expenditure ,the company and the taxpayer related will have a poorer payable ability,so it can curb the economy overheating.in the other hand,when the economy is in the state of recession,the government may increase expenditure,as above,the company and the taxpayer related will have a stronger payable ability.
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