Breakdown of yínháng dòngjié le yínhángkǎ.
Used after a verb. Marks that an action is completed.
Questions & Answers about yínháng dòngjié le yínhángkǎ.
Here, 了 marks that the action has been completed.
So 冻结了 means something like:
- froze
- has frozen
- did freeze
It does not mean past tense in exactly the same way English does. Instead, it often shows completion of the action. In many contexts, that naturally gives a past meaning.
Compare:
- 银行冻结银行卡。 = The bank freezes / will freeze bank cards / the bank freezes the card (more general, habitual, or context-dependent)
- 银行冻结了银行卡。 = The bank froze / has frozen the bank card