Converting declarative sentences into interrogative sentences involves changing the statement into a question. This usually requires rearranging words and using appropriate auxiliary verbs. Below are the transformed sentences:
I sang a classical song.
Did I sing a classical song?
Mr. Prabhat walks to his office.
Does Mr. Prabhat walk to his office?
Rohan is running in the park.
Is Rohan running in the park?
We finished the game easily.
Did we finish the game easily?
There are five million rupees at risk.
Are there five million rupees at risk?
London is the capital of England.
Is London the capital of England?
The teachers have treated us kindly.
Have the teachers treated us kindly?
The scientist was always absorbed in his work.
Was the scientist always absorbed in his work?
To make these changes, you typically place the auxiliary verb before the subject. For sentences in simple past or simple present without auxiliary verbs, you add 'do/does' or 'did' at the beginning, based on the tense.
This process allows you to transform statements into questions, which is a useful skill in writing and conversation to seek information or clarification.