Formatter strings use numbered variables like %1$s to indicate parts that should be replaced by other text.

• %1$s will be replaced by the distance, like "in 500 meters."
• %2$s will be replaced by the direction, like "make a right turn."
• %3$s will be replaced by the name or number of the street or exit, like "Main Street" or "Exit 123."

For example "%1$s %2$s onto %3$s"
becomes "In 500 meters make a right turn onto Main Street"

whereas "%3$s is the place to %2$s when you reach it %1$s"
becomes "Main Street is the place to make a right turn when you reach it in 500 meters."