Liu Meng Xi (刘梦溪) is a Chinese name, and when translated to English, it can be broken down as follows:

• Liu (刘) is the surname, which is a common Chinese surname.
• Meng (梦) means "dream" in English.
• Xi (溪) means "brook" or "stream" in English.

So, the full name Liu Meng Xi can be translated to "Liu Dream Brook" or "Liu Dream Stream" in English.