Use the right prepositions or adverbs: every morning ten o'clock, when her lecture jean the room, where i was work. her careful, accurate work was of great me. she prepared slides which it was necessary to examine. she was very careful and never made a mistake. her presence stimulated me o'clock we had the the seventh day, as we worked silently i heard a step and professor challis stood doorway "i thought i'd look in, robert, to see how you were getting on. i rose at once and introduced jean. he bowed in his old-fashioned manner i understood that he liked her. .that he came regularly to visit us, the lunch hour he sat chair watching us with his bright eyes. he often told his life as a young student sorbonne, where he worked under the great duclaux. (from "shannon's way" by a. cronin)