3.In each of the following groups of words, there are four underlined letters or letter combinations marked A, B, C and D. Compare the underlined parts and identify the one that is different from the others in pronunciation.

• A、useless
• B、endless
• C、unless
• D、hopeless

57.

What is the main idea of the passage?

• A、Exercise strengthens people's body

• B、Exercise helps babies to grow.

• C、Exercise improves people' s lif

• D、Exercise benefits the brain.