问题补充：
— Shall I turn on the TV, Mom?
—No. You should be quiet wake up your sleeping brother.
A. so not as to
B. so as not to
C. so as to not
D. not so as to
答案：
A. so not as to
B. so as not to
C. so as to not
D. not so as to
解析： 考查状语。句意：妈妈，我能开电视吗？不，你应该保持安静，为的是不吵醒睡觉的弟弟。So as not to do 为的是做某事 ，故选B项。
考点 :考查状语
