________ as the “first lady of speech”，Dr, Lillian Glass is recognized as one of the world's leading experts on communication skills.
| A．Knowing | B．Having known |
| C．Known | D．To be known |
It was the training he had as a young man made him such a good engineer.
| A．what; that | B．which; that | C．that; which | D．that; what |
Once harm ______ to the environment, it takes years to have the system recovered.
| A．does | B．is done | C．will be done | D．be done |
Last night my neighbors ______ such a loud noise at the party that I couldn’t sleep at all.
| A．were making | B．are making | C．had made | D．have made |
Exciting as its special effects are ______, there is too much violence in the film.
| A．to watch | B．to be watched | C．watching | D．being watched |
Young people who have got jobs may realize university lessons can’t be the only preparation for all the situations _______ appear in the working world.
| A．where | B．when | C．that | D．what |