Key Concepts:
The use of "shall" and "will" in interrogative sentences is an important aspect of English grammar. These modal verbs are used to express future actions or intentions.

Usage Examples:
1. Shall I help you with your homework? (क्या मैं आपकी होमवर्क में मदद करूँगा?)
2. Will you come to the party tomorrow? (क्या आप कल पार्टी में आएंगे?)
3. Shall we go for a walk in the park? (क्या हम पार्क में सैर करेंगे?)
4. Will she be able to attend the meeting? (क्या वह मीटिंग में शामिल हो पाएगी?)

Key Mistakes:
1. Confusing the use of "shall" and "will" in interrogative sentences. Remember, "shall" is used with the first person (I and we), while "will" is used with the second and third person (you, he, she, it, they).
2. Using "shall" or "will" in negative interrogative sentences. Instead, use "shall not" or "will not" to form negative interrogative sentences.

Learning the correct usage of "shall" and "will" in interrogative sentences is essential for effective communication in English. Practice using these modal verbs in different contexts to improve your language skills.