After the summer vacation the professor together with his fellow teachers the scientif

问题补充：

After the summer vacation, the professor, together with his fellow teachers, the scientific experiment

A. goes down

B. go down

C. gets down to

D. get down to

答案：

A. goes down

B. go down

(答案→)C. gets down to

D. get down to

解析：考查主谓一致。together with连接两个主语时，谓语动词取决于前者，get down to 开始认真做某事。句意：暑假之后，这位教授和他的同伴老师们开始专心于科学实验。故选C。