Question

8. At that time Einstein        his opinion and went on with his research.

   A. kept on   B. stuck to

   C. insisted on   D. went on

Answer 1

8. B stick to意为"坚持，不离弃(=refuse to leave;continue to believe sth. although it may be difficult) ",往往指坚持某一观点、信仰等。keep on意为"坚持不停地做某事(=do sth. without stopping) "，相当于go on ( with sth. / doing sth. ) ;insist on (doing sth.) 意为"坚持做(尤指麻烦或令人讨厌的事) (=keep doing sth.，especially sth. that is inconvenient or annoying) "。