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the largest type of cargo ship is a tanker. the tankers are designed to carry 1.___ liquid cargo such as 2.___ oil. The cargo is pumped directly into 3.___ holds by 4.___ powerful pumps.  5.___ holds are constructed as 6.___ tanks. 7.___ tanks are sub-divided into 8.___central tank, two wing tanks and 9.___ expansion tank. 10.___ expansion tank allows 11.___ oil to expand in hot weather. 12.___ bridge superstructure and 13.___ and 14. ___ engine room are situated aft to leave more room for 15.___ cargo. 16.___bridge is connected to 17.___ forecastle by 18.___catwalk. 19.___tankers which are over 500,000dwts are known as 20.___ ultra large crude carriers.