In the city the old _______.
It was in the lab, ________ was taken charge of by Professor Curie, _______ they did the experiment.
The answer ________ the teacher,she asked the little boy to try a second time.
There is a saying which _______like this:, “Still waters run ______.”
Chemical processes _______in the treatment of materials for clothes _______the environment badly in some countries nowadays.
.In the last ten years she _____ like this; she is killing her health.