The quoted line had ' used to ' as an adjective in the sense ' habituated'. As a modal auxiliary it is not used. The verb phrase is 'had been'. When ' used to' is a modal auxiliary, it means habitual action in the past and doesn't have verb conjugation except omission of infinitival 'to' after it. In this sense, your substitution is incorrect.
Barid Baran Acharya
- 2.4k
- 13
- 15