[解析]
M:Anna,when did the Smiths ask us to get to their house?
W:By 7:30 pm.There are just thirty minutes to go.Are you ready to go now?
M:Not yet.Do you know where my blue shirt is?I don't want to go in this brown one.
W:It's right there in the cupboard with your other shirts.Why isn't Sara here yet?She said she'd be here by 7:00 pm.Without her taking care of the kids,we can't go to the Smiths'tonight.
M:Don't worry.I'm sure she'll be here any minute now.It takes us just about twenty minutes to get there.We won't be late as long as we leave by 7:10 pm.