In which sentence is the underlined phrase an adjective clause? A male platypus can eject venom when another animal disturbs it. The platypus, which is a mammal, has a bill like a duck and feet like an otter. When explorers first sketched the platypus, scientists thought the sketches were a hoax.
An adjective clause is a dependent clause that, like an adjective, modifies a noun or pronoun. Adjective clauses begin with words such as that, when, where, who, whom, whose, which, and why.