sentence starting with <是我和我...> what does it mean?

定 vs. 订 both mean "sign", so, what's the difference? what is the difference? if i sign a contract etc., how do i say? which of them is used in the situation when i need to sign a document?

听说 vs. 说 what is the difference between these two? if use it in sentence like this: (or some others?) 听他们说，明天我们驶向海边。 他们说， 明天我们驶向海边。

how to say in chinese "they say,..."; "one says, ..."; "people say, that..."; "i would say...".. in german it sounds like "man sagt..." ; "man sagt das..."

how to say "this is a fake", "fake money", "fake paper", ... in mandarin there is this fake paper, you know, if you live in china, you would know it... but how to call it? how chinese people call this fake paper? when someone would give you this sort of "a good job", how would you react? (in chinese) in your opinion, what does a person need to say in that situation? (in chinese) please, give examples ^_^