某手扶拖拉机厂电工张某，自恃技术熟练，在检修电路时，不按规定操作，造成电路着火，使部分设备烧毁，损失4万多元。张某的行为构成何罪

A．失火罪

B．破坏集体生产罪

C．重大责任事故罪

D．玩忽职守罪

I ___________ at school now, but I _________ at home an hour ago.[ ]

A. am, am

B. was, was

C. am, were

D. am, was