像下面如此的句子，because if...屬什么的生肖結構？既是緣由狀語從句，也是條件狀語從句？這是一種什么語法現象？

He had to sTOP talking because if he’d kept on, the stuttering would have started.他不能不停止講話，由于假如他繼續下去，口吃就會發作。

I didn’t give my name because if I did I thought you might not have come.我沒留下我的名字，由于假如我這么做的話，我想你可能就不會來了。

because從句本身是個主從復合句。if從句是修飾后面的句子的。將if從句移至句末就了解了。

He had to sTOP talking because the stuttering would have started if he’d kept on.他不能不停止講話，由于假如他繼續下去，口吃就會發作。

I didn’t give my name because I thought you might not have come if I did.我沒留下我的名字，由于假如我這么做的話，我想你可能就不會來了。