The English Tense in Passive Voice

Those constructions are all rare because they are too cumbersome, and so shorter constructions are used instead. It is exquisitely difficult to construct a contextual framework in which the longer version would make more sense than the shorter one.

They are also too confusing. All those markers of a continuous aspect are superfluous in all but the rarest of circumstances, especially when combined with a completed aspect.

1. shall/will be being offered

This should normally be simply shall/will be offered without the being part:

• It’s not being offered now.
• It will be offered later.
• We will be offering that later on.

2. has/have been being offered

3. had been being offered

These two try to combine a perfect construction (have + past participle) with a continuous aspect (be + present participle). The speaker should make up their mind about whether the action is completed or continuing.

• It hasn’t been offered lately.
• It hadn’t been offered yet.
• It wasn’t offered yet.
• It wasn’t being offered yet.
• It hadn’t been offered yet.
• We weren’t offering that then.
• We hadn’t been offering that way back then. (poor)
• We didn’t offer that way back then. (better)
• We weren’t offering that way back then. (also better)

4. shall/will have been being offered

This has the same problem as before: a confusion of continuous and completed aspects. Use only one.

• It will be offered then.
• We will be offering it later.
• It will have already been offered by then.