Mywalletisnowheretobefound.I_____itwhenIwasonthebus.
D
must have+done 用于推断过去某个时间肯定发生了的事情。
_____alltherepresentativesstillnotthere，themeetingwaspostponedforseveralhours.
Theteachergave_____theexaminationpaper.
“Itwasverycoldtesterday.”
“_____.”
Hisarticleisbetterthan_____intheclass.
