The Sleepy Dog<br>The dog laid down beside her, yawning. He was obviously tired from playing all day. He curled up in a ball so he could sleep. He flopped onto his back after a while. He just laid there, waiting for a tummy rub.
The dog had never had a tummy rub before, which is why he was waiting for one.
If the dog had never had a "tummy rub" he wouldn't know to roll on his back to get one.
( z1 rub :polarity - :ARG1 ( z2 tummy :part-of ( z3 dog ) ) :time ( z4 ever ) :time ( z5 before ) :ARG0-of ( z6 cause :ARG1 ( z7 wait :ARG1 z3 :ARG2 z1 ) ) )