经前综合症的确切病因尚未完全了解。

The exact causes of PMS are not fully understood.

youdao

目前其确切病因和发病机制不详。

Its exact etiology and pathogenesis remain unknown.

youdao

更确切的病因还不清楚。

The exact cause is not known.

youdao

医生能治这种病，不过他不能指出确切的病因。

The doctor was able to treat the disease although he could not put his finger on the exact cause.

youdao

遗传是患病因素之一，但确切的机制并不清楚。

Heredity is a predisposing factor, but the exact mechanism is unclear.

youdao

其确切的病因和发病机制目前尚未明确。

The exact etiology and mechanism is unknown.

youdao

其确切的病因和发病机制目前尚未明确。

The exact etiology and mechanism is unknown.

youdao