PHP: is the implode() function safe for multibyte strings?

The explode() function has a correlating multibyte-safe function in mb_split() .

Split a sentence into separate words

I need to split a Chinese sentence into separate words. The problem with Chinese is that there are no spaces. For example, the sentence may look like: 主楼怎么走 (with spaces it would be: 主楼 怎么 走 ).