根据句意和首字母或汉语提示，将单词的正确形式写在题中相应的横线上。
There’s nothing in this box. Look, it’s e______________.
You’d better to keep your v______________ down when talking in public.
Jack is so smart that he can answer these questions ______________ (容易地) .
Both of my best friends were born in ______________ (十月) .
People will use robots to do the ______________ (家务) in the future.