lcannot function as weapon: it is made of hollow hones filled with air, so it is thin and lightweight; If it is used as weapon, it will be easily damaged.
lthey have to call out to each other in order to use the color and shape to blend into surroundings. If they do this, they are going to draw attention from predators
lHealthy toucan do not use their bills: they need bill to get rid of heat in the daytime but at night when the temperature is lower, they then need to retain body heat.
Independent writing task
Do you agree or disagree with the following statement: It is as important for older people to study or learn new things as it is for younger people.
Firstly, learning new things can help older people keep pace with the developing world and take advantage of its benefits. With the advancement of science and technology, our society has been undergoing great changes every day. For example, people used to consult maps before going to different places in old days, but with the application of positioning in most mobile phones, people no longer need to bother with such inconveniences. Facilitation brought by these innovations enable younger people as well as older people to live a more convenient life.