There is a good question. In this case, it is a preposition.
a subject
An introductory phrase or clause is often used as a sentence opener. This allows for varied sentence structures and can help to provide context or background information before the main subject of the sentence is introduced.
Yes, "however" can be used as a clausal opener to introduce a contrasting or concessive idea in a sentence. It is often followed by a comma when used in this way.
What kind of sentence? The kind of sentence in which the word kind is being used. Oh, thank you. That was very kind.
A sentence opener is a word that will start a sentence. You can have all types of sentence openers including verbs, adverbs, connectives, adjectives, similes, metaphors, feelings and much more.
He is a kind person.
The first sentence in a paragraph. It givesm the reader and idea of what the paragraph/essay is going to be about.
Yes, an opener can be in the middle of a sentence as long as it is set off by punctuation such as commas. For example, "However, despite his efforts, he still did not succeed."
A pronoun opener introduces a pronoun in a sentence and helps avoid repetition of a noun. For example, in the sentence "Mary went to the store. She bought groceries," "She" is the pronoun opener that refers back to Mary without restating her name.
In most cases yes.
The design of the tin-opener was simplistic in the extreme. It consisted of two small metal parts hinged together.
Adverb