Most of the stars are much more bigger than the sun, but they are _______ light-years away from us.

完形填空

　　The sun, the moon and the stars are all in the sky．The earth 　　1　　 round the sun．And the moon circles(围绕)the earth．

　　The sun is 　　2　　 than the moon．It gives us light and heat(热量)．When our part of the earth turns 　　3　　 the sun, it is day．When our part of the earth turns away 　　4　　 the sun, it is night．“Morning”is the time 　　5　　 sunrise(日出)and twelve o'clock, the 　　6　　 is overhead(当头)．It is“noon”．And when the sun sets(日落), it is“evening”．

　　The moon is much smaller than the sun．It 　　7　　 bigger only because it is much 　　8　　 the earth．It is our nearest neighbour(邻居)in space(宇宙)．Sometimes it looks quite bright, but it 　　9　　 any light at all．The light on the moon 　　10　　 from the sun．It only reflects(反射)the 　　11　　 of the sun．

　　The stars look 　　12　　 than the sun and the moon．But 　　13　　 of the stars are bigger than the sun．　　14　　 look small because they are very far away from 　　15　　．