As in much previous work (Yu and Ballard, 2007;Fazly et al., 2010), we take child-directed utterances from the CHILDES database (MacWhinney, 2000) in order to have naturalistic data.
we use the Manchester corpus (Theakston et al., 2001), which consists of transcripts of conversations with 12 British children between the ages of 1; 8 and 3; 0.