2. The Think Tank at the National Zoo in Washington, DC, is
an exhibit that is unique. The project, which scientists call
the Think Tank (“a place to think about thinking”) examines
the biological thinking process of animals. Scientists, who
have different opinions about which animal behaviors
actually involve thinking, say thought has three elements:
image, intention, and flexibility. The scientists at the Think
Tank are studying these elements in many different animals,
but it is the orangutans who are seen as the stars of the
exhibit because they are learning to use symbolic language
on a computer.
2
3. Use who or that as the subject of an
adjective clause.
who
Scientists who have different opinions about
animal behavior, say thought has three
elements.
3
4. Use who or that as the subject of an
adjective clause.
that
The Think Tank at the National Zoo in
Washington, DC, is an exhibit that is unique.
4
5. Use who(m), which, that, or Ǿ as the object
of the verb in an adjective clause.
The project examines the biological thinking
process.
Scientists call the project the Think Tank.
The project, which scientists call the
Think Tank, examines the biological
thinking process.
5
6. Practice 1
Choose all the possible completions.
1. The Think Tank is an exhibit ___ is very interesting.
a. who b. that c. which d. Ǿ e. whom f. it
2. The scientists ___ work there are studying “thinking.”
a. who b. that c. which d. Ǿ e. whom f. they
3. Let’s go to the new exhibit ___ Tom told us about.
a. who b. that c. which d. Ǿ e. whom f. it
6
7. Practice 1
Choose all the possible completions.
4. It’s the scientists ___ are studying the orangutans.
a. who b. that c. which d. Ǿ e. whom f. they
5. The Think Tank is a place ___ I’d like to visit.
a. who b. that c. which d. Ǿ e. whom f. it
6. The study ___ goes on all day is open to the public.
a. who b. that c. which d. Ǿ e. whom f. it
7
8. The orangutans are the ones whose language ability is
being examined. Four orangutans are being trained to use a
special computer which is set up so they learn around 70
different symbols. These symbols, which consist of seven
categories such as food and verbs, use simple shapes. For
example, a rectangle by itself means “food”. Scientists want
to see if once the orangutans learn the symbols, they can
putwords together to express thoughts. The orangutans visit
the Think Tank when they want, and their participation is
voluntary. The building where they live is linked to The Think
Tank by cables that they can travel back and forth on. On
days when they go to the Think Tank, they can choose if
they want to participate or just watch. 8
9. Use whose to show possession in
adjective clauses.
whose
The orangutans are the ones whose language
ability is being examined.
Whose language ability is
being studied?
The orangutans.
9
10. Use when to modify a noun of time
in adjective clauses.
when
On days when they go to the Think Tank,
they can choose if they want to participate
or just watch.
What does ‘when” refer to?
On days they go to the
Think Tank.
10
11. Use where to modify a place.
where
The building where they live is linked to The
Think Tank by cables.
The building
Which place is
“where” referring to? The Think Tank
11
12. Practice 2
Make one sentence out of the two sentences by
using adjective clauses.
1. The Think Tank is in the zoo. All this activity takes place is
in The Think Tank.
The Think tank, where all this activity takes
place, is in the zoo.
2. The scientists study the animals. The animals are awake
then.
The scientists study the animals when they are
awake.
3. Here are some children. Their parents have brought them to
the zoo.
Here are some children whose parents have
brought them to the zoo.
12
13. Review
Complete the sentences. More than one answer
may be possible. Discuss your choices.
1. The symbols have no visual relationship to the
words _____ they represent.
a. who b. that c. which d. Ǿ e. whom f. where
2. The Think Tank is the only place in the world _____
visitors have free access to this type of research.
a. who b. that c. which d. Ǿ e. where f. when
13
14. Review
Complete the sentences. More than one answer
may be possible. Discuss your choices.
3. The words _____ the orangutans are learning will
be used to form simple sentences.
a. who b. that c. which d. Ǿ e. whom f. where
4. How do the orangutans make the connection from
the word to the thing _____ it represents?
a. who b. that c. which d. Ǿ e. whom f. when
14
