用括号里所给动词的适当形式填空。
It is said that walking under a ladder means bad luck, and it's the same with black cats. People 1______
(say) if a Mack eat crosses before you, it 2______ (bring) you bad luck, too. But I didn't think so until I heard
my student Sam's story this afternoon. Ever since then, I 3______ (begin) thinking about whether it is true.
This afternoon, Sam walked down the street thinking about when 4______ (hold) a party for his girlfriend,
so he didn't notice where he was going. When he 5______ (walk) right under a ladder standing against a
building, a black cat ran out of a door, which surprised him and made him 6______ (fall) over. His head hit the
ladder. The man who was cleaning the window at the top of the ladder fell down, and the dirty water 7______
(go) down through the air. Poor Sam! He got wet all over.
B(?)+ 2C(?) △H＞0，满足如图所示的关系，则下列说法中正确的是 