1.he ()carefully ,but he ()nothing.A listen ,hear B listen ,heard C listened ,hear

问题描述:

1.he ()carefully ,but he ()nothing.A listen ,hear B listen ,heard C listened ,hear
D listened ,heard
2.if you don't ()carefully ,you can't ()the sound.
A hear ,listen B listen ,listen to C hear ,hear D listen ,hear

1.D
2.D
比较:listen(to)表示听,指听的过程,hear表示听到,指听的结果.