Please check.

[WZ]

Please help explain:

1. Do we use "come on board" for "ships" only? Can I use it for "bus", "train"?
Are these two sentences OK:
- By the time the train left, all the passengers have come on board.
- By the time the train left, all the passengers have boarded.

2. Do we always use plural nouns (countable) after phrases like "a box of..."?
And in "pair of N", if I want to add an adjective, should I put it before "pair" or before the noun? E.g. "long pair of pants" or "pair of long pants"? "Blue pair of jeans" or "pair of blue jeans"?

Thanks.

[Rusty]

Please help explain:

1. Do we use "come on board" for "ships" only? Can I use it for "bus", "train"?
Are these two sentences OK:
- By the time the train left, all the passengers have come on board.
- By the time the train left, all the passengers have boarded.

2. Do we always use plural nouns (countable) after phrases like "a box of..."?
And in "pair of N", if I want to add an adjective, should I put it before "pair" or before the noun? E.g. "long pair of pants" or "pair of long pants"? "Blue pair of jeans" or "pair of blue jeans"?

Thanks.

1. Do we use "come on board" for "ships" only? (No).
Can I use it for "bus", "train"? (Yes).
Are these two sentences OK:
- By the time the train left, all the passengers had come on board. (OK).
- By the time the train left, all the passengers had boarded. (OK).

2. Do we always use plural nouns (countable) after phrases like "a box of..."? (If the noun is countable, use a plural after "a container of....").

And in "pair of N", if I want to add an adjective, should I put it before "pair" or before the noun? E.g. "long pair of pants" or "pair of long pants"? "Blue pair of jeans" or "pair of blue jeans"? (Putting the adjective before the noun sounds more natural. I'm not sure if there is a rule).