若x和y都是buble型变量，且x的初值为3.0，y的初值为2.0，则表达式pow(y,fabs(x))的值为 【7】 。

用 come about, happen, take place,  break out, occur 的正确形式填空

①I was out of town at the time, so I don't know exactly how it ________.  

②The meeting _________  at 8:00 as planned.  

③It   ________  to rain that morning.  

④A fire ________ in the hotel last night.  

⑤It suddenly _________ to me that I ha left my key in the office.