1.tk is a network term, which means diving, voyeurism, voyeurism and so on. It can be used to watch others talk instead of talking in group chat, or it can be a way of tickling.

2.tk is the abbreviation of thymidine kinase in the book retrieval number, and it can also be a national top-level domain name.

Please note that the meanings of network terms and abbreviations may change with the changes of time and context, and it is recommended to refer to specific situations when understanding them.