问题补充：
Tom kept silent about the accident lose his job.
A. so not as to
B. in order not to
C. in order to not
D. not so as to
答案：
A. so not as to
(答案→)B. in order not to
C. in order to not
D. not so as to
解析：考查固定词组，in order to意思“为了”，so as to意思“为了”，其否定式都是把not放在to的前面，in order to既可以放在句首又可以放在句中；so as to只放在句中，所以选B
