Definition:
to assume a certain role, task, or position means to take it on and become responsible for it.
Examples:
1. The new CEO assumed control of the company.
2. I assumed responsibility for the project.
3. He assumed the position of team leader.
Tips:
When using the verb form of 'assume,' it's important to remember that it must be paired with an object (i.e., responsibility, position, task, role, etc.). Thus, when using it in a sentence, make sure there is something immediately after it that explains further what is being assumed.