sentences:  The monitors were originally black-and-white, but were replaced by color ones in 1988.Most bus routes serving downtown Portland followed the transit mall, but a few remained on so-called "cross-mall" routings, along east-west streets, originally Morrison and Yamhill streets but shifted to Washington and Salmon streets with the start of MAX construction in the early 1980s.With regard to operations, the mall was designed with two bus stops in each block, or about one stop every .