信号防护子系统功能由机顶框实现，机顶框由（）、（）和（）组成。
参考答案：DMLC单板；DELC单板；DSAC单板
All his classmates________his happiness when he won first prize in the competition. [ ]
A. shared
B. shared from
C. shared with
D. shared like
依法行政是依法治国的核心和关键。
