How can you replace the word was in this sentence He a smart child?

Here are some ways to replace "was" in the sentence "He was a smart child":

Keeping the meaning the same:

* Is: He is a smart child. (Present tense)

* Has been: He has been a smart child. (Present perfect, emphasizing a continued state)

* Used to be: He used to be a smart child. (Past tense, implying a change)

* Was considered: He was considered a smart child. (Passive voice, emphasizing perception)

Changing the meaning slightly:

* Seems: He seems like a smart child. (Implies an observation)

* Appears: He appears to be a smart child. (Implies a belief)

* Could be: He could be a smart child. (Implies possibility)

For a more informal style:

* He's: He's a smart kid. (Contraction for "He is")

The best replacement depends on the context and the intended meaning.