捕食。
参考答案：
是指一个物种的成员取食另一个物种成员的现象。
His father is a worker, he often works _________ night. [ ]
A. at
B. in
C. for
D. during
为减小交流接触器的振动和噪声，常在铁芯上加（）。
A.弹簧
B.短路环
C.缓冲器
