The migrant workers who rescued a woman trapped in a sinkhole on a Singapore road over the weekend have drawn widespread praise, but their actions have also reignited debate over the conditions these labourers face, especially the contentious issue of transporting them in the backs of lorries.The rare incident occurred on Saturday evening along Tanjong Katong Road South, when a black Mazda was swallowed sideways into a three-metre (10-foot) deep cavity filled with murky water. Video footage...