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A．after he worked in the same company for less than 25 years
B．after he worked in different companies for 25 years
C．after he worked faithfully in the same company for over 25 years
D．after he worked heart and soul in his own company for 25 years

A．The retired engineer overcharged for his service.
B．The retired engineer happily went to examine the machine.
C．The retired engineer changed the broken part for a new one.
D．The retired engineer did find out what was wrong with the machine.