TOEFL ShortRead 3

What is the passage mainly about?

• Faint dwarf stars

• The evolutionary cycle of the Sun

• The Sun's fuel problem

• The dangers of invisible radiation

What does the author say is especially important about the Sun at the present time?

• It appears yellow

• It always remains the same

• It has a short history

• It is too cold

Why are very hot stars referred to as "ghosts"?

• They are short- lived.

• They are mysterious.

• They are frightening.

• They are nearly invisible.

According to the passage as the Sun continues to age, it is likely to become what color?

• Yellow

• Violet

• Red

• White

In line 15, to which of the following does "it" refer?

• yellow hump

• day

• Sun

• hydrogen fuel