Semibluff any of these?

[Womble]

I find myself in lots of these situations. I have a good draw and everyone is checking but I can't bet for value as there arent any opponents.

Party Poker 1/2 Hold'em (6 max, 6 handed) converter

Preflop: Hero is BB with 7[img]/images/graemlins/diamond.gif[/img], 4[img]/images/graemlins/diamond.gif[/img].
<font color="#666666">1 fold</font>, MP calls, <font color="#666666">2 folds</font>, SB completes, Hero checks.

Flop: (3 SB) J[img]/images/graemlins/diamond.gif[/img], K[img]/images/graemlins/heart.gif[/img], A[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(3 players)</font>
SB checks, Hero checks, MP checks.

Turn: (1.50 BB) 2[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(3 players)</font>
SB checks, Hero checks?


Party Poker 1/2 Hold'em (6 max, 6 handed) converter

Preflop: Hero is BB with 9[img]/images/graemlins/diamond.gif[/img], 8[img]/images/graemlins/club.gif[/img].
<font color="#666666">1 fold</font>, MP calls, <font color="#666666">1 fold</font>, Button calls, <font color="#666666">1 fold</font>, Hero checks.

Flop: (3.50 SB) 2[img]/images/graemlins/club.gif[/img], Q[img]/images/graemlins/spade.gif[/img], 7[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(3 players)</font>
Hero checks, MP checks, Button checks.

Turn: (1.75 BB) T[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(3 players)</font>
Hero checks, MP checks, <font color="#CC3333">Button bets</font>, Hero?


Party Poker 1/2 Hold'em (6 max, 4 handed) converter

Preflop: Hero is BB with 8[img]/images/graemlins/spade.gif[/img], 9[img]/images/graemlins/spade.gif[/img].
UTG calls, Button calls, <font color="#666666">1 fold</font>, Hero checks.

Flop: (3.50 SB) 4[img]/images/graemlins/diamond.gif[/img], 2[img]/images/graemlins/diamond.gif[/img], 6[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(3 players)</font>
Hero checks, UTG checks, Button checks.

Turn: (1.75 BB) K[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(3 players)</font>
Hero checks, UTG checks, <font color="#CC3333">Button bets</font>, Hero?

You get the idea! I folded/checked these when they happened and thought it was correct but it kept happening throughout the session. Some hit, some didnt but what is profitable?