Compléter Container Ship (fill in the blanks)Version en ligne English for Navigation - Teacher: Paula D. Cava par Paula DC 1 Container ships transport a combination of two container sizes known as 20 - or 40 - feet equivalent units . The are carried in cellular and stacked on the ships hatch covers and upper . The contents of the containers can be non - perishable , or perishable , with the latter often being carried in containers . Container shipping generally operates according to regular on set routes , known as ? liner ? services . For this reason , the sector is sometimes referred to as ? liner shipping ? . ships have played a key role in the of products over the past twenty years , enabling consumer goods and products to be in developing , lower cost countries for to higher cost countries .