1. Is a noun always the subject of a sentence?
No. While nouns are often the subjects of sentences, they can also serve other roles:
* Direct Object: The noun receives the action of the verb. Example: "The dog chased the ball." (Ball is the direct object)
* Indirect Object: The noun receives the direct object. Example: "She gave him a gift." (Him is the indirect object)
* Object of a Preposition: The noun follows a preposition (words like "to", "from", "with", etc.). Example: "The cat sat on the mat." (Mat is the object of the preposition "on")
* Subject Complement: The noun renames or describes the subject. Example: "He is a doctor." (Doctor is the subject complement)
2. Can some ideas?
This question is a bit unclear. Could you please rephrase it?
For example, do you mean:
* Can ideas be nouns? Yes, ideas can be nouns! Example: "The idea of flying a kite is fun."
* Can some ideas be expressed in sentences? Yes, ideas can be expressed in sentences.
Please clarify your question, and I'll be happy to help further!