1.Our ship isn't in the port now
Is our ship in the port now?
2.The junior engineer doesn't help motorman with his work.
Does the junior engineer help motorman with his work?
3.There aren't many sailors on deck.
Are there many sailors on deck?
4.Our engineer doesn't have friends in Singapore.
Does our engineer have friends in Singapore?
5.That navigator isn't reading a chart.
Is that navigator reading a chart?