My sister never stop talking, while my brother doesn't talk much. He is a little bit shy. 是说妹妹总爱说话对吧？然后弟弟不怎么爱说话...那么我不清楚为了brother后面只有一个空 应该有两个才对.. 这是我认为正确的答案，希望可以帮到你！
