The ship sails in the sea
The ship sails on the sea
The ship sails the sea
Which one ?
Help me teacher..
They can sail on the sea.
They can be in the middle of the sea.
They can sail the sea.
The difference between sailing "on the sea" and sailing "the sea" is that the first is a very basic sentence suggesting that ships travel along the surface of the water, while the second says that they sail all over the seas.
We had a recent thread about the difference between travelling in a country and travelling a country.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.