电力变压器的油起( )作用。
Heblamedhispoorperformance_____jetlag.
Ifyou_______inbehavinginthiswayyouwillbringyourselfnothingbuttrouble.
支持代孕的理由有
Thetwogirlscompetedwitheachother______thehighestmark.
Ifhe_____thestorekeeper‘sscissors，hewouldhaveforgottentobuyapair.
