All of them try to use the power of the workstation ______ information in a more effective way.

单项选择题We（）on this project for four hours. Let's have a rest.

A. are working
B. have been working
C. worked
D. had worked

单项选择题Galileo lived in the City of Pisa, ______ there is a leaning tower about 180 feet ______.

单项选择题She didn't see me come and went on ______ her newspaper.

单项选择题The air of countryside is cleaner than ______ of city, but I don't like to live ______ far.

单项选择题Madame Curie's ______ encouraged many women to study science, and many of them ______.