没有这一点，所有的讨论都无从谈起。

Without this point, no discussion can be started.

但如果天然气的生产过程是不清洁的，那么它的成本低廉就无从谈起。

But if natural gas is not produced cleanly, it will not prove to be so cheap, either.

如果噪声源和抗噪波无法重合，合成波形就不能恰好重叠，抗噪效应也就无从谈起。

Unless the sources of the noise and the antinoise coincide, the wave patterns will not overlap properly and the effect will be lost.

加之中国戏剧中的以假嗓歌唱，又模糊了男女声的界线，和声自然更无从谈起。

In addition, the fake singing in Chinese drama has blurred the confines of female and male's voice without mentioning the harmony.

我在1991年至1994年间担任路透中国分社社长，当时"透明"几乎无从谈起：数据不可靠，采访机会寥寥无几，中国经济状况对外界来说还是一个谜。

When I was Reuters China bureau chief from 1991 to 1994, there was almost no transparency; statistics could not be relied on; interviews were rare; the state of the economy was a mystery.