Question

Mr Mehta has decided to travel by _ sea to Bangkok​

Answer 1

Answer:

the is the answer

Explanation:

Answer 2

Answer:

There is no need for an article as it makes sense beforehand itself. Over here, the sentence requires no article as by sea is correct and by the sea will be wrong.  Here, it means that Mr. Mehta decides to go to Bangkok by a ship that mean by sea.

Example, Mr Mehta decided to go to Bangkok by air it wont be by the air.

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