In most of those cases, the "u" would have once been pronounced with a bit of a y-sound at the beginning: mez-yoor, trez-yoor, yooz-yual.

大多数情况下，u的发音曾今在开始的时候带有一点y音。mez -yoor, trez - yoor, yooz -yual。

youdao

In most of those cases, the "u" would have once been pronounced with a bit of a y-sound at the beginning: mez-yoor, trez-yoor, yooz-yual.

大多数情况下，u的发音曾今在开始的时候带有一点y音。mez -yoor, trez - yoor, yooz -yual。

youdao