be under no illusion
US /biːt əˈraʊnd ðə bʊʃ/
UK /biːt əˈraʊnd ðə bʊʃ/

1.
no hacerse ilusiones, ser consciente
to understand the true facts of a situation and not have false ideas
:
•
You should be under no illusion about the difficulty of this task.
No debes hacerte ilusiones sobre la dificultad de esta tarea.
•
We are under no illusion that this will be easy.
No nos hacemos ilusiones de que esto será fácil.