If you mean 'What preposition would you use to describe train travel?' the answer is 'by': 'I will go by train when I visit my aunt in Edinburgh.'
However, 'train' has other meanings, for example, to prepare for something. In that case it is a verb, not a noun. So you would say 'The athlete will train for the Olympics.'
You will get a much better answer if you express your question as a complete sentence. It is also more considerate towards the people who you hope will help you. I have made two guesses at what you might mean, but both of them may be wrong. I should not really have to spend time guessing what you mean.
either a noun or a verb
The preposition is through.The noun 'tunnel' is the object of the preposition.Through
No. Whom is the objective form of the pronoun "who." It is not used as a preposition.
Ere is a preposition that is a palindrome.
No, then is not a preposition. It is a conjuction.Than is a preposition.
No. Almost is an adverb. It is not used as a preposition.
At is a preposition. Anything that can be ___ the box is a preposition. For Example: At the box.
Yes. Because can be used as a preposition.
The preposition is into.The prepositional phrase is into a rage.
No, the word "when" is not a preposition. It is an adverb or a conjunction used to indicate time or a condition.
It is almost always used as a preposition.
Yes. It is a preposition used in a comparison