Thanks a lot for your answer, but I've heard of lots of possible, feasible, and real situations using conditional2, such as
"If you went to the street, you would see the sign"-going to the place can be very casual, not a difficult thing.
"I actually have plans for Tuesday, but I'd be interested in meeting another time this week" - This is from my canadian friend.
He said it when I postponed out meeting, but meeting another time in that week was not that unlikely, it could have been possible, not like to win lottery.
and the following is from wikipedia extract for the definition of future conditional 2,
and it says the difference between conditional1 and conditional2 is slight, so it seems to say the two are sometimes interchangeable.I need your clear answer again as I'm always confused about this.
In many cases, when referring to future events, the difference between a realis and irrealis conditional is very slight:
(realis) If you leave now, you can still catch your train.
(irrealis) If you left now, you could still catch your train.