On following sentence the first clause is a dependent clause. The second clause is an independent clause which can stand by itself.

Before President Roosevelt died, President Truman did not know that the United States was developing atomic weapons.

I say No Noun Clause. My professor is moving so fast with different types of clauses that it gets confusing to me. Thank You for the help

You're right. The dependent clause is an adverb clause, not a noun clause.

http://www.chompchomp.com/terms/adverbclause.htm

In the sentence you provided, "Before President Roosevelt died" is the dependent clause, and "President Truman did not know that the United States was developing atomic weapons" is the independent clause.

To determine whether a clause is dependent or independent, you can look for a few key indicators.

1. Dependent clauses often begin with subordinating conjunctions like "before," "unless," "since," or "while." In this case, "Before" is the subordinating conjunction that introduces the dependent clause.

2. Dependent clauses cannot stand alone as complete sentences because they don't express a complete thought. They rely on an independent clause to provide the full meaning. In this sentence, "Before President Roosevelt died" does not express a complete thought and needs the independent clause to make sense.

On the other hand, independent clauses can stand alone as complete sentences because they express a complete thought and can function independently.

In your example sentence, "President Truman did not know that the United States was developing atomic weapons" is a complete thought and could stand alone as a sentence.

Therefore, the first clause, "Before President Roosevelt died," is a dependent clause, and the second clause, "President Truman did not know that the United States was developing atomic weapons," is an independent clause.