additional ironing meaning in English

每增加一次熨烫

Biotechnologists have developed genetically modified rice that is fortified with beta - carotene - - which the body converts into vitamin a - - and additional iron , and they are working on other kinds of nutritionally improved crops
生物技术专家已经培育出了含有?胡萝卜素(身体可将之转化为维生素a )和更多铁元素的转基因水稻，目前正在研究培育其他一些增进营养成分的农作物。