单项选择题
The detective and his assistant have begun to （）the mysterious murder.
A．look into B．see to C．make over D．come through
单项选择题 The wood was so rotten that, when we pulled, it （）into fragments.
单项选择题 This movie is not （）for children to see: it contains too much violence and too many love scenes.
单项选择题 Very few people understood his lecture, the subject of which was very （）
