来自蔡岩的问题
句型转换IthappendthatIwasoutdoorswhenthefirebrokeoutI-----------outdoorswhenthefirebrokeout
句型转换IthappendthatIwasoutdoorswhenthefirebrokeout
I-----------outdoorswhenthefirebrokeout


句型转换IthappendthatIwasoutdoorswhenthefirebrokeoutI-----------outdoorswhenthefirebrokeout
句型转换IthappendthatIwasoutdoorswhenthefirebrokeout
I-----------outdoorswhenthefirebrokeout
happenedtobe
happento是碰巧的意思,后接动词原形,且此题为过去时,所以用happenedtobe.