The main purpose of subheadings are:
They stand out because of their size and attract attention.
The scanner will stop to read them and continue scanning until the next subhead which they'll then read.
It is romanticized because they both I committed suicide at the thought of having to live without each other.
The correct answer is one main clause.
This means that there is only one verb in the sentence, which in this case is the verb 'was.' Even though drive is also a verb, in this context it is used as an adjective driven (participle form of the verb to drive) and is thus not considered to be a verb. This means that there are no subordinate clauses but rather just one main clause.
There is an envelope marked with the instructions that it is not to be opened until the death or disappearance of Dr. Jekyll. This implies that Dr. Lanyon knew something secret, but was unwilling to reveal it at first. He waited until there was no more "hope" of Dr. Jekyll staying normal.
William Butler doesn't like time, he feels bad about aging and going through the days.
