He yakked on endlessly about his wife.

于他的妻子, 他喋喋不休地说个没完。

The jokes get yaks.

那话引。

Only because yak is living in remote area and oxherd, with low knowledge,  has less communication with outside world , the yak is less heard and popular as sheep and milk cow.

只因牦牛栖息在偏远地区，养畜牦牛的牧民又甚少与外界接触，知识水平都普遍低下，以致牦牛的经济价值不及和乳牛般广为知。