form·a·tive
adjective/ˈfɔːmətɪv/
/ˈfɔːrmətɪv/
[only before noun]- having an important and lasting influence on the development of something or of somebody’s character
（对某事物或性格的发展）有持续重大影响的 - the formative years of childhood
童年性格形成的时期 - formative influences in the development of the labour movement
对工人运动发展的形成性影响
Oxford Collocations DictionaryFormative is used with these nouns:- experience
- influence
- period
- …
Word Originlate 15th cent.: from Old French formatif, -ive or medieval Latin formativus, from Latin formare ‘to form’, based on Latin forma ‘a mould or form’. - the formative years of childhood