Identify the imperative sentence:

• The required answer is - Please open the window.

• Imperative Sentence:
- An imperative sentence is a type of sentence that gives a command, makes a request, or provides instructions. It is used to express a direct order or to ask someone to do something.
- সাধারণত, Subject উহ্য রেখে Verb দিয়ে শুরু হওয়া বাক্য imperative sentence হয়ে থাকে. তাছাড়া imperative sentence বাক্যে আদেশ, নিষেধ, উপদেশ, অনুরোধ বুঝায়।

• প্রদত্ত অপশনগুলোর মধ্যে,
- "Please open the window" is a polite request, making it an imperative sentence. It instructs someone to open the window.

• উল্লিখিত বাকি অপশনগুলো,
- Where are you going? - Interrogative sentence.
- He is reading a book. - Assertive sentence.
- I will call you tomorrow. - Assertive sentence.

Source: A Passage To The English Language S. M. Zakir Hussain.