For some people, the sight of a mouse can be reason to scream. For other mice, the same sight can be reason to sing.
Mice will probably   1   sing their way to any concert, but researchers in the United States have found   2   that mice do,   3  , sing.
Scientists already knew that mice make ultrasonic(超声波) sounds—noises that are too high-pitched(高音的) for people to hear   4   special equipment.
To find out whether mice put such sounds together in song-like   5  , the researchers recorded the sounds of 1 mice. Using computer   6  , they were able to separate the sounds into specific types of syllables(音节), and found the mice produced about 10 syllables per second.
The results showed that nearly all of the mice repeated sequences(顺序) of syllables in different patterns. That’s enough to meet the definition of what scientists   7   song. But not all scientists are   8  _ that what the mice are doing is   9   singing. To prove it, the researchers must show that there’s learning involved. And, they need to __  10   why the mice sing.

A．almost B．even C．never D．usually

A．coincidence B．evidence C．guidance D．instance

A．at once B．by means C．for example D．in fact

A．during B．inside C．through D．without

A．fashions B．instructions C．patterns D．styles

A．access B．printer C．screen D．software

A．call B．hear C．sing D．write

A．accustomed B．convinced C．involved D．qualified

A．actually B．obviously C．simply D．unlikely

A．figure out B．get about C．run across D．talk over