use of lots/gifted/snack/subway

[Hardwork]

Are these sentences grammatically correct and please let me know the corrections if wrong.
1) I am in the subway(railystation subway)
2) Is snack always plural or singular
3) He was gifted with such tiffins at/on his wedding.(should we use at/on)
4) what is the difference between lot and lots

[Mordant]

"Snack" is singular and "snacks" plural.

3) I looked up "tiffin." It sounds to say someone was gifted with a meal at his wedding, so I have to ask what you mean. As for your own question, it is "at a wedding" and "on a wedding day."

4) I guess you mean the difference between "a lot" and "lots." There is none, except that the latter is even more informal and probably indicates an even greater abundance.

[Beeesneees]

'Tiffin' is a light meal, originally particularly a meal at lunchtime it is now related to afternoon tea.

Most people wouldn't use it (unless they were making fun of someone they considered to be 'snobbish').
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