If you join this room, vs If you know this roon,

Some examples from the web:

• If you leave this room, you are finished with my team.
• In this room, you shall discover if you possess the Sight.
• If you are in this room, it is because you reside in my innermost circle of trust.
• If you leave this room, I calculate Trent Hauser will be killed in prison.
• If you leave this room, I calculate Trent Hauser will be killed in prison.
• If you're going for the least modern man in this room, congratulations, you have won.
• For now if you're in this room, you have your assignment.
• I don't know how many men you have left in your game, but if you're leaving this room, it needs to be a small army.
• Because we know if you're in this room, You've got loads of it.
• However, outside this room, if you withhold information about the case, you and your company will be held fully accountable.
• If you have the air in this room, you don't notice each individual atom.
• But if you look around this room, there isn't one thing that wasn't recorded, written or filmed in the last two years.
• However, outside this room, if you withhold information about the case, you and your company will be held fully accountable.
• If you leave this room, I will find you in contempt.
• This room, if you want, is yours.
• You join this union, you make it strong.
• Everybody in this room, if you stay alive, is going to be affected by what's happening in cities in this extraordinary phenomenon.
• So, if you lay in the bed in this room, it's said you'll come up with crazy theories.
• Now, I know him better than anyone in this room, and if you shut this down, you lose all hope of stopping him.
• I agreed to let you join this task force with the promise that family wouldn't be an issue.

Some examples from the web:

• If you know this program, turn him in.
• If you know this guy, we're looking to interview him.
• If you talk with somebody suffering, you know this makes a difference.
• Anyway, let's see if you know this junk.
• If you know this number, you can use it when required.
• Now I don't know if you know this, but we fought in the war together.
• I don't know if you know this, but we Fells are notorious busybodies.
• I don't know if you know this, but I am really bad at Christmas shopping.
• I don't know if you know this about me, but I've coached a few models in my time.
• I don't know if you know this about fat people...
• I don't know if you know this, but my cousin Kyle's pretty hurt.
• I don't know if you know this about me, Kenny, but the gene for jealousy... recessive.
• You know, if you're looking for a cameraman, I actually know this great indie film director who just thinks that shooting the sector would be amazing.
• Sheila, if you know this kid, better tell her to get lost.
• I don't know if you know this, but there is a band outside your door.
• I don't know if you know this, but I attended Harvard University.
• I don't know if you know this, but when Kai merged with Luke, he went through a metamorphosis.
• I don't know if you know this, but that's a pretty standard item in an assisted-living facility.
• I don't know if you know this, but bacteria can actually exchange DNA.
• No more talk about me. I don't know if you know this, but I used to be self-centered.