[xorbie]

Depends a lot on his play. A lot of people will call a flop with a wide range of holdings all of which they are going to fold to a later bet. If this person isn't going to put more money in without improving, you should bet again to protect the pot. OTOH, some people will view your bet, check line as weak and bet. Against these people I like to bet flop, check call turn and lead river (or check call again).