池塘里传来的鸭叫声打破了清晨的宁静。

The ___quacks from the pond broke the morning silence.

那个江湖郎中自称能治百病，其实是个骗子。

That man pretending to cure all diseases is just one of those ___quacks.

池塘里的鸭子不停地嘎嘎叫。

The ducks in the pond keep ___quacking loudly.