pick out the subordinate clause and state its kind:He attended school because he was bored with online lectures​

The subordinate clause is: because he was bored with online lectures.

It is an adverbial clause.

Explanation:

To find a subordinate clause in a sentence, we must find the subordinating conjunction. In this case, the subordinating conjunction is "because", which means the subordinate clause is:

"because he was bored with online lectures."

A subordinate clause, or dependent clause, cannot stand on its own as a sentence, since it cannot convey a complete meaning alone. It needs to be connected to a main clause, and that is precisely the function of the conjunction (connecting).

In this case, the subordinate clause is functioning as an adverb, which makes it an adverbial clause. Adverbial clauses modify a verb, an adjective, or an adverb in the sentence. They often answer questions such as when, where, why, how, etc. In the sentence we are analyzing here, we could ask why he attended school, and the answer would be "because he was bored with online lectures."

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