The part of the sentence "which role to" is not correct or usable in written English.
In order to use it correctly, you could change it to 'which role does' or 'which role should'. For example: I can't decide which role does he play in this project.
The contacts I made before applying helped me to think about where I would best fit in the firm, so I made an educated decision about which role to apply for.
What an expected scene, everyone knowing which role to play, the outcome never changing.
Within role theory, a number of concepts have emerged: role confusion, which refers to dilemma in deciding which role to take on; role embracement, which refers to holding a role so much that the self disappears; and role strain, which refers to tensions from incompatible expectations within a role.
If you are a bit uncertain of which role to choose in an instanced dungeon, try to be a damage dealer instead of a tank or a healer.
If you've been pursuing two different careers (perhaps in preparation for a career move) you can choose which roles to include and which to delete.
While he has the confidence to decide which roles to accept, he also jokes about being able to control very little of his film career.
There are many other considerations regarding which roles to fill with manager types.
A direct role of human endogeneous retroviruses in Schizophrenia has not been established, so it is not clear to me which role needs to be explained.
This work is an extended version of conference ACIIDS 2017 paper: [15] in that article, we simulated a quantum circuit based on kNN algorithm which role was to classify the Hermitian and non-Hermitian matrices.
For brief periods in 1906 and 1909 10 he served as prime minister, in which role he proved to be unable to conciliate parliament.
Bana had read the book Lone Survivor prior to production, and was willing to appear in the film, regardless of which role was offered to him.
