1.   He flagged a cab, then checked the dashboard for license and ID, since assaults are spiralling out of control in Mexico City these days.

2.   He wears horn-rimmed glasses when flagging a cab because, he says, they make black men appear less threatening.

3.   Then they flagged a cab for downtown and the bus station.

4.   They flagged a cab.

5.   To flag a cab on these streets today is to ask for trouble.