Question

my uncle has left for bombay last saturday../ find error in the sentence

Answer 1

has is the error.
had should be the right one!!

Answer 2

Answer:

My uncle had left for Bombay last Saturday.

Explanation:

Past tense implies that the action has been done long back and has been completed. It refers to any action done previously. Past tense has four forms – the simple past, the past continuous, the past perfect and the past perfect continuous form.  

In this sentence, the past perfect tense has been used where the verb has been written in the participle form. As last Saturday has been mentioned, the time aspect has been given and we know that the action had already been done. So had left is correct and has left is wrong.