Do the following sentences say the same thing?
But other sources close to the sale said Vivendi was keeping the door open to further bids and hoped to see bidders interested in individual assets team up.
But other sources close to the sale said Vivendi was keeping the door open for further bids in the next day or two.

4

Do the following sentences say the same thing?
The man is riding a horse.
A man is riding on a horse.

5

Do the following sentences say the same thing?
How would Martin not know that that was not the case?
How would Martin or anyone else know his intentions based on his actions?

2

Do the following sentences say the same thing?
nuclear weapon systems at a high level of readiness increase the risk of those weapons being used including unintentionally with catastrophic consequences.
the resolution says that the high level of readiness increases the risk of the use of such weapons and that the unintentional or accidental use would have catastrophic consequences.
4