When I entered the classroom I found the student

I found a letter lying on the floor when I came into the classroom.（)

Entering the room, I found my father______at the desk and______something.A．seat... writeB．

I had scarcely passed my twelfth birthday when I entered the inhospitable regions of exami

For the past two years I have been working on students evaluation of classroom teaching.

When I entered the lab she()(make)an experiment.

I arrived in the classroom ready to share my knowledge and experience with 75 students who would be