in English is:

protectionism

Mutations

Soft:ddiffynnaeth
Nasal:niffynnaeth
Aspirate:(no mutation)

Use

y ddiffynnaeth hon
fy niffynnaeth i
dy ddiffynnaeth di
ei ddiffynnaeth ef/o
ei diffynnaeth hi
ein diffynnaeth ni
eich diffynnaeth chi
eu diffynnaeth nhw/hwy
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