"Can the key still be used?" is a question that could be asked in Engpsh to determine if a key is still functional or not.

The phrase "can still be used" is a way of expressing that something is still capable of being used or performed. It suggests that the thing in question may have been used or performed before, but it is not yet broken or worn out.

Here are some examples of how this phrase could be used in a sentence:

"Can this car key still be used to start the car?"
"Is this pen still usable, or do I need to buy a new one?"
"These old pots and pans have been in my family for generations, but they can still be used for cooking."

In Chinese, the phrase "还能用吗" (hái néng yòng ma) could be used to ask the same question. The word "还" (hái) means "still" or "yet," and "能用" (néng yòng) means "can be used." The particle "吗" (ma) is used to turn the statement into a question.