You will be given a definition of a task first, then some input of the task.
In this task, given a sentence in the English language, your task is to convert it into English Tokens.

The breakthrough involves a gene known as TRESK, thought to control the brain's reaction to pain: if it is defective, then many normal activities and actions will be painful.
Output:
The breakthrough involves a gene known as TRESK , thought to control the brain 's reaction to pain : if it is defective , then many normal activities and actions will be painful .