As it turns out lots of drivers don't understand an attached single traffic light, private cars are like this, professional goods vehicles are also like this, it seems that when some drivers see two traffic lights showing at the same time they don't know what they should do.
原來好多人都唔識睇孭仔燈，私家車係噉樣，搵食貨車又係噉樣，好似同時閃兩吓燈都有啲人睇得唔青楚應該點做。