Question

no sooner had the thief see the policeman then he fled.make affirmative​

Answer 1

Answer:

Here is your answer...

As soon as the thief see the policeman, he fled.

Answer 2

The given sentence can be made an affirmative sentence as shown below:

The thief had hardly seen the policeman when he fled.

or

As soon as the thief saw the policeman, he fled.

Explanation

No sooner….than…is an idiomatic expression which means something happens immediately after something else. We have to use this expression together. It means whenever we use ‘no sooner’, we will always have to use ‘than’ with it.  

Similarly, we can use the expressions 'as soon as' and 'hardly' to convey the same meaning.