He does not know what he is doing，but he breathes(呼吸)as well as the oldest and cleverest man in the world．He began to breathe when he was born，and he will not stop until he dies，still he does it without thinking about it．

See how long you can hold your breath．

In some places men dive(潜水)in the sea for pearls (珍珠)．They pick up shells(贝壳)that hold the pearls，and the longer they stay under water，the more pearls they can find．For the reason(原因)they hold their breath as long as they possibly can．Yet even these pearl divers can't go without breathing for a long time．

Watch to see how many times a man draws his breath every minute．Some men breathe fifteen times a minute．An elephant breathes only eight times．It was told that a mouse breathes a hundred and twenty times each minute．

No one needs to tell us that what we breathe every minute of every day is air．It is around us everywhere，like wonderful sea that we can not see．

1．Everyone began to breathe ________． (　)

A．when he is old

B．when he is clever

C．when he was born

D．when he was a child

2．What do the men dive in the deep sea for? (　)

A．They want to hold their breath．

B．They want to make their bodies stronger．

C．They want to find pearls．

D．They want to find reasons for breath．

3．A mouse breathes ________ times more than an elephant every minute． (　)

A．105

B．120

C．112

D．15

4．The word “It” in the last paragraph(段)means ________． (　)

A．wonderful sea

B．air

C．a mouse

D．an elephant

5．Which of the following is NOT TRUE in thepassage? (　)

A．We can't live without air．

B．The babies also need to breathe．

C．The dead also need to breathe．

D．Animals need to breathe every minute．