Before his maize is stolen, the maize he stores at the end of 1 year is 12*1= <<12*1=12>>12 tonnes of maize.
Before his maize is stolen, the maize he stores at the end of 2 years is 12*2= <<12*2=24>>24 tonnes of maize.
After his maize is stolen, he is left with 24-5=<<24-5=19>>19 tonnes of maize.
After he receives the maize donation, he has 19+8=<<19+8=27>>27 tonnes of maize.
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