It was in the lab ______ was taken charge of by Professor Harris _______ they did the experiment.

Progress so far has been very good____,we are sure that the project will be completed on time[ ]

Is your brother a League member?—Yes, he____ the League threeyears ago. He____ a League member for three years

Reading her biography, I was in admiration for __________ Doris Lessing had achieved in literature.

He failed to_________ himself to the new environment.[ ]