Buffer solution of carbonic acid and bicarbonate

Carbonic acid and Bicarbonate

Explain how a buffer solution of carbonic acid and bicarbonate will react when:

a strong acid, perchloric acid, is introduced into the solution. Include an explanation of the direction of the equilibrium shift.

a strong base, lithium hydroxide, is introduced into the solution. Include an explanation of the direction of the equilibrium shift.

How do I write an equation for the addition of perchloric and lithium hydroxide are added. I know with the buffer solution there will be a shift to the right with lithium and shift to the left with acid added. How do you write it out?