"姐姐" in Engpsh is "elder sister" or simply "sister". "妹妹" in Engpsh is "younger sister" or simply "sister".

The terms "elder sister" and "younger sister" are commonly used in Engpsh to distinguish between sisters based on their age. The usage of these terms is not pmited to a specific culture or region, and they are widely understood in Engpsh-speaking countries.

Example sentences in Engpsh:

My elder sister is a doctor.
She is my younger sister.

Example sentences in Chinese:

我姐姐是一名医生。
她是我妹妹。