I wonder why he has been acting sostrangely these days—Recent pressure at work may ____ hisbehavior

When exposed to stress, in ________ form, all of us react both chemically and physically.

It is along time _______they separated, but it won’t be long ____ they meet again.

I stand up and see many students_______out of the classroom.

Such animals like dinosaurs died out because they couldn’t _____ to the change of the climate.