Jeremy Harmer in his book The Practice of English Language Teaching says:
"Developmental errors: for a long time now researchers in child language development have been aware of the phenomenon of 'over-generalisation'. This is best described as a situation where a child who starts by saying Daddy went, They came, etc. perfectly correctly suddenly starts saying *Daddy goed and *They comed. (...) Foreign language students make the same kind of 'developmental' errors as well". (p. 100). We can infer that:
