"Belated as they may be", "expensive as they may be". Can someone please explain the structure of these sentence as to what exactly does "as they may be" mean and how it is used ?
Belated as they may be
The above is not a complete sentence. Normally, such phrases are the middle of a complete sentence or the end of a complete sentence. For example:
Please accept my commiserations, belated as they may be.
The adjective "belated" is used to describe the nature of the subject such as the noun "commiseration" in the example above. The phrase "as they may be" is used to indicate that the "commiseration" is heart-felt, even though it is late in delivery.
My offers to help, belated though they were, were gleefully accepted.
The example above is slightly different since the phrase "belated though they were" appears in the middle of the sentence. The meaning of the above example is that the offers to help were happily accepted even though they were late or delayed.
Further similar examples (hopefully self-explanatory):
Those few precious memories, treasured as they were, were tossed aside in a fit of rage.
In his sorrow, the Emperor stared at those glistening jewels in the palms of his hands. Then, as precious as they were, he let those precious stones fall into the sea.