I have to underline the dependent clause and tell whether it is an adjective, adverb, or noun. Can you help me with the following.

If you sit down with a novel and a dictionary, you can refer to the dictionary often.

Still what morph means remains the critical question.

If you sit down with a novel and a dictionary, you can refer to the dictionary often.

Dependent clause: If you sit down with a novel and a dictionary

Adverb clause modifying the verb, "can refer."

In the sentence still what morph means remains the critical question.

Is the dependent clause still what morph means?

Is it an adverb describing the clause remains?

Dependent clause: what morph means

Noun clause used as the subject of the verb "remains."

I am really not understanding this at all.

How a word begins and ends often gives clues to its meaning.

Dependent Claus how a word begins and ends.

Adverb modifying what it gives?

No.

What is the subject of the verb, "gives"?

The obvious answer is the dependent clause: How a word begins and ends

Study this site carefully. Note that it refers to noun clauses as nominal clauses.

http://www.towson.edu/ows/advadjnomclause.htm

The subject of the word gives is the dependent Claus?

Yes, in this sentence, that is true.

In these two I am torn between adverb and noun.

If all else fails, go to the dictionary.

If you are familiar with the word metamorphosis, you might figure out the meaning of morph from that word.

The top one noun?

The bottom one adverb?

Both of those are adverb clauses.

Note that the subject of the verb, "go" is the understood subject (you).

Thanks.

How about this one.
For example, since amorphous ends in ous, it is probably an adjective.

Dependent Claus since amorphous ends in ous,
Adverb?