Hold'em table

42o is far too weak to open raise or call, even from the button.

Q5o is too weak to complete or raise out of position against the big blind after the button folds, so folding the extra 50 is the lower-variance choice.

26o is too weak to open even on the button, so folding is the highest-EV play.

Heads-up against the big blind, 85o is weak but calling only 50 into a 150 pot gives 3:1 odds, making this a clearly profitable limp rather than folding or raising a marginal hand.

In position against the small blind limp, A2o has showdown value and plays reasonably well, so checking back to see a free flop is standard.

I hold 5-high with no draws on an A-J-J board, so betting has little value and calling a bet would be costly. Checking keeps the pot small and gives a free chance to improve.

I hold top pair with a weak kicker on a paired flop in position. Checking behind controls the pot size and allows me to realize showdown value or evaluate on future streets.

I hold 8-high with no pair, no draw, and essentially no showdown equity on J-J-A-Q. Checking is free and keeps the pot small; I'll fold to any bet rather than bluff into the big blind's checked-back range.

We hold top two pair with a weak kicker on a coordinated board. Checking back controls the pot and realizes showdown value safely against check-raises or disguised hands.

My 5-high holding plays as just a pair of jacks off the board, which loses to any pocket pair or jack that would have raised by now. Checking back keeps the pot small and avoids paying off a stronger showdown hand.

I have two pair, Aces and Jacks, with a Queen kicker. Betting is unlikely to get called by worse hands given the board texture, so checking behind takes down or chops the pot safely.

Pocket queens on the button are a premium hand; I raise for value and initiative rather than just calling, building the pot while keeping control with position.

AKo is a premium holding in the small blind facing a button open, making a 3-bet to 11 bb standard for value and isolation.

62 offsuit is too weak to continue against a raise and a 3-bet; folding saves chips.

Pocket queens are far ahead of a 3-handed SB 3-betting range; calling in position keeps their bluffs and dominated hands in while letting me fold cheaply on A/K-high boards or value bet Q-high ones.

I flopped top pair top kicker on a king-high board as the preflop 3-bettor, so I make a standard small continuation bet for value and protection.

Only 700 to call into a 3000 pot, and QQ retains solid equity against a wide 3-max 3-betting range on this K-high board. Raising would fold out the JJ/TT/AQ hands I beat while isolating AA/KK/AK, so calling and re-evaluating the turn is best.

I have trip Kings with top kicker. Betting small extracts value from pocket pairs and flush draws while keeping their calling range wide.

74s is too weak to open profitably from the button even in 3-handed play.

Five-deuce offsuit is too weak to complete or raise from the small blind after the button folds. Folding avoids playing a dominated hand out of position.

K2o is too weak and disconnected to open from the button; folding avoids reverse implied odds and dominated spots.

Q3o from the button is a weak hand; with only two opponents behind and no pot odds worth chasing, folding preserves chips for better spots.

Holding an unsuited 8-2 in the small blind is well below the threshold to complete or raise, making a fold the clear standard play.