Question

if i (know) his address,i would have contacted him.

Answer 1

Answer: The correct word to use in this sentence is “knew.”

So we can rewrite the sentence as “If I knew his address. I would have contacted him. Tense is very important while constructing a sentence to make it grammatically right".

Here, as one id describing some act that would have been done therefore past tense should be used t make the sentence correctly constructed.

Answer 2

Explanation:

If I had known his address, I would have contacted him.