他是一位资深的内科医生。

Tā shì yī wèi zīshēn de nèikē yīshēng.

He is a senior internal medicine doctor.

他是一名内科医生。

Tā shì yì míng nèikē yīshēng.

He is a general medicine doctor.

你应该要去看内科医生。

Nǐ yīnggāi yào qù kàn nèikē yīshēng.

You should go see an internal medicine doctor.