Question

I was not sure if it was you ( begin - I was doubtful)

Answer 1

I was doubtful if it were you

Answer 2

I was doubtful whether it was you.

The above sentence means that the narrator felt doubtful whether it was the listener or not.

1. Doubtful means having queries or having doubts regarding something or someone or something that is unsure, suspicious, or unclear.

2. An example of something doubtful is a condition or situation that is reported by any person who consistently lies.

3. Let us take some examples with the word "doubtful"-

# His voice was doubtful over the call and she let the topic drop.

# Eliza looked doubtful, but she didn't natch him.

#SPJ3