tā / suī / rán / zhī / dào / shì / qing / de / zhēn / xiàng / ， / què / shǐ / zhōng / bì / kǒu / bù / tán / 。

她虽然知道事情的真相，却始终闭口不谈。

Although she knew the truth, she remained tight-lipped about it.