7 sentences

1. 我奶奶今年九十岁了。

   wǒ nǎi​nai jīn​nián jiǔ​shí suì le.

   My grandmother is ninety years old this year.

   Source: Dong Chinese Dictionary

2. 这件事我有九十趴的把握。

   zhè jiàn shì wǒ yǒu jiǔ​shí pā de bǎ​wò.

   I am ninety percent sure about this.

   Source: Dong Chinese Dictionary

3. 老人家已九十高龄，但体格依然康强。

   lǎo​rén​jiā yǐ jiǔ​shí gāo​líng, dàn tǐ​gé yī​rán kāng qiáng.

   The elderly man is ninety years old, but his physique is still robust.

   Source: Dong Chinese Dictionary

4. 去掉最高分和最低分，平均分是九十分。

   qù​diào zuì​gāo​fēn hé zuì dī fēn, píng​jūn​fēn shì jiǔ​shí fēn.

   Excluding the highest and lowest scores, the average is ninety.

   Source: Dong Chinese Dictionary

5. 虽然他已经九十岁了，但生活还能自理。

   suī​rán tā yǐ​jīng jiǔ​shí suì le, dàn shēng​huó hái néng zì​lǐ.

   Even though he is ninety years old, he can still manage his daily life.

   Source: Dong Chinese Dictionary

6. 爷爷虽然已经是九十岁的高龄，但依然耳目聪明，视力极好。

   yé​ye suī​rán yǐ​jīng shì jiǔ​shí suì de gāo​líng, dàn yī​rán ěr​mù cōng​ming, shì​lì jí hǎo.

   Although my grandfather is already ninety years old, his hearing is still sharp and his vision is excellent.

   Source: Dong Chinese Dictionary

7. 听说你的爷爷虽然已经九十岁了，但依然健在，真是好福气。

   tīng​shuō nǐ de yé​ye suī​rán yǐ​jīng jiǔ​shí suì le, dàn yī​rán jiàn​zài, zhēn shì hǎo fú​qi.

   I heard your grandfather is still alive and well at ninety years old; you are truly blessed.

   Source: Dong Chinese Dictionary