i have to get to cambridge from london kings cross for a family matter , can you help me book a train ?
user
yes , i can help . what day do you need to leave ?
assistant
i would like to leave on sunday .
user
is there a certain time you want to leave after or arrive by ?
assistant
i would like to leave after 17,15 on sunday .
user
tr1681 leaves at 19:17 and arrives 51 minutes later . how is that ?
assistant
perfect . i'll need 2 tickets .