Actus reus - Infliction of Grievous bodily harm (GBH)
S.20 uses the word 'inflict'.
This word has been interpreted widely.
S.18 OAPA 1861 has the same actus reus as s.20, except it uses the word 'cause' instead of 'inflict'. The Courts have confirmed that these two words should be defined the same in this circumstance.