AA 2925 then CZ 438 at O'Hare
Boston → Chicago → Shanghai
Timetable, Chicago time
21:54AA 2925 from Boston at the gate
18:25CZ 438 to Shanghai leaves the gate
20 h 31 apart on the timetable, overnight
CZ 438 leaves 20 h 31 after AA 2925 arrives on the timetable: more than half a day, so not a connection we count.