Texas holdem game strategy changes drastically if there is a pair on the board. This is not an automatic fold when holding a draw to a flush or straight, but in many cases should be.
The situation must offer above average pot odds and implied odds to continue. A good rule of thumb is if you have any doubts and the pot is not laying extremely good odds, then folding is best. If it is best to continue in a big multi-way pot do not use texas holdem strategies like semi-bluffing or pot building. Just try to draw as cheaply as possible. Poker Authors first to share this...
Also how many players are in the pot, how strong there actions are, and the texture of the board should give you some info of whether or not you are facing a full house. A flop with AAQ for example is much more dangerous than 227. Due to the fact it is more likely someone is going to be playing a type of hand like AQ then 227. Depending on the game of course.
The more players in the pot the more likely someone either already has a full house or trips and drawing to one which takes away some of your out to complete your hand. Or worse could mean you are drawing dead.
And the same idea applies if there is more betting and or raising than normal. It should be a tell or at least a warning sign something might be wrong.
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