可以幫忙翻譯這段嗎 - 金融業討論

有兩段英文敘述如下本人看不大懂
麻煩專業人士解釋一下
感謝

A purchase of securities by the central authority(central bank) injects funds
into the banking system. This causes an expansion of liquidity because the proceeds of
selling securities to the central bank releases funds into the banking system.


A sale of securities by the central bank leads to a reduction of funds in the
banking system. This is called a contraction of liquidity and occurs because
funds are withdrawn from the banking system to buy the securities from the
central bank.

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