Final answer:
The 'ct' and 'pt' endings in English words come from Latin origins. Words like 'strict' and 'act' derived their 'ct' from Latin words 'strictus' and 'actus'. Similarly, 'pt' in 'erupt' comes from the Latin word 'eruptus'. Also, words ending in 'ct' often take '-or' suffix to form nouns which denote the doer of the action, another convention borrowed from Latin.
Step-by-step explanation:
The 'ct' and 'pt' endings in English words often originate from Latin, where these combinations were common. For instance, in the word 'strict', the 'ct' comes from the Latin word 'strictus', meaning 'tightened'. Similarly, for the word 'act', the 'ct' is derived from the Latin word 'actus', meaning 'a doing'. The use of 'pt' in words like 'erupt' also originates from Latin, in this case from 'eruptus', the past participle of 'erumpere', meaning 'to burst forth'. As for words that end in 'ct' taking the '-or' suffix to sell the doer of the action, this is another convention borrowed from Latin, such as 'actor' meaning 'doer', originally derived from 'actus', the past participle of 'agere', meaning 'to do'.
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