While working in the countryside, the students a great deal of knowledge on plant life.

May I see you at 4 o’clock thisafternoon—— I’m afraid not, I acharity meetingthen.

Not knowing where to go or what to do, I ______ across the streets aimlessly .

_____ the night, we did nothing but _____ there, waiting for him to come

Our English teacher is ill, and we are all ______ her health.