unprompted
adjective uk/ʌnˈprɒmp.tɪd/ us/ʌnˈprɑːmp.tɪd/
主动的，自发的，未经敦促的
without being told to say or do something
Jim was remarkably charming this evening - he even said, unprompted, how nice Margot looked in her dress. 吉姆今晚格外招人喜欢——他甚至主动赞美玛戈穿那件连衣裙很漂亮。