Toefl exam Essentials

LISTENING
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1. Locate the main idea. The main idea of a
conversation, class discussion, or lecture is different
from its main topic. The topic is the subject—what a
conversation or lecture is about. The main idea is what
the speaker wants to say or express about the subject.
The main idea is a general statement that brings
together all of the ideas in a conversation or talk.
Here’s an example. Listen to an instructor begin a lecture:
Today we’re going to talk about the body’s immune system. As
you may know, the immune system is what defends the body from
infections. It’s really a remarkable system—in the body, millions
and millions of cells, organized into sets, or smaller units called
subsets, make a complex communications network that pass infor-
mation back and forth, almost like bees swarming around a
hive. The result is a sensitive system of checks and balances the
produce a prompt, appropriate, and effective immune response.