By Longhand Limit Hold’em we mean a game with 8 or more players. It’s not like Shorthand game. The main difference is that you have to be more patient than in Shorthand games.
Your cards Be patient because you have to wait until you’re dealt good cards. Not the question is – what are the good cards? First of all look at the David Sklansky’s Groupings. So what hands are considered to be playable? You can surely raise at preflop with:
JJ through
AAAK
If someone raised you can call with the same hands. You can also call (but don’t insist – I mean don’t call three bets cold) with these hands:
TT
99
88
AQ
KQ With other hands you shouldn’t call a raise. The chance that you’ll be beaten is to big. So be very careful with:
AJ
AT
KJ
QJ
JT
QT With other hands – depends on the situation, on the flop that comes. For example, if you have something like 76 then you’ll be happy to see something like 45J on the flop. Also you can call if other players limped.
Example Let’s suppose that your hole cards are:

So three players limped and you’re the last to act. You stay in game. The flop is:

What will you do if one of the players raises very aggressively? It seems that you have the second best hand. Then it’s better for you to act as if you’re on a draw. Or fold.