If you work harder, you'll have another______ to play the violin at a concert.
A:sleep
B:chance
C:mistake
D:problem
I played a game on the computer,and it ______ working.
把肯定句改成否定句。
①我对同学们的勇敢精神,从心底里感到无限的敬佩。
③信赖,往往创造出美好的世界。
关于声现象,下列说法正确的是( )