“有四种”造句
有四种专门广播频道, 播放不同类型的节目.
There are four specialized radio channels, which broadcast different kinds of programmes.
这就是说, 包括两个空位在内,总共
有四种孔型.
That is, if we include the double blank there are four patterns.
目前已经知道
有四种寻常情况会产生这种效果.
Four general circumstances which lead to this effect are konwn.