Who is to _____(blame)?

Who is to _____(blame)?
为何答案是blame 而不是be blame? 整句个人翻译起来应该是"谁该被责怪?"不用被动么?

lame 是及物动词,一般用blame sb (for...).
但,在习惯用法be to blame中表示被动意义：应该受责备.
He is to blame .
blame 不用被动.
He is to blame for the accident.他应在事故中负责.
英语辅导报高三版：从高考题谈 blame 的用法
请看下面两道高考题:
1.The mother didn't know______to blame for the broken glass as it happened while she was out.(NMET2002)
A.whoB.when C.howD.what(答案为A)
2.I feel it is your husband who______for the spoiled child.(2002年上海高考)
A.is to blameB.is going to blameC.is to be blamedD.should blame
(答案为A)
以上两道高考题均考查了blame的用法.下面详细介绍一下该词的用法.
一、blame用作及物动词时,通常用于下面三个句型:
1.blame sb.for sth./doing sth.为某事责备某人/责备某人做了某事.如:
Many children are afraid of being blamed for making mistakes in speaking English.许多孩子害怕讲英语时犯错误而受责备.
He blamed his teachers for his failure.他把自己的失败归咎于他的老师.
His companion,blamed for the accident,had not been driving carefully.他的同伴没有谨慎驾驶,应对事故负责.
2.blame sth.on sb.把某事归咎于某人.如:
The police blamed the traffic accident on Jack's careless driving.警察把那起交通事故归咎于杰克的粗心驾驶.
It's no use blaming our defeat on him.把我们的失败归罪在他头上是没用的.
She blamed the failure of their marriage on him.她把婚姻的失败归咎于他.
3.be to blame (for)应(为……)承担责任;该(为……)受责备.[注意]此处不能用被动语态.如:
The children were not to blame for the accident.那次事故怪不着孩子们.
He is more to blame than you.是他更应受责备,而不是你.
Who is to blame for starting the fire?这场火灾该由谁负责?
I am in no way to blame.决不该责备我.
二、blame用作名词时,常用于下列搭配:
1.accept/ bear/take the blame for sth.对某事负责任.如:
You must bear the blame for the accident.你必须承担造成这次事故的责任.
We were ready to take the blame for what had happened.我们愿对所发生的事负责.
2.put/lay the blame for sth.on sb.将某事归咎于某人.如:
She'll put the blame on us if it turns out badly.如果结果糟糕,她将会怪罪于我们.
He is trying to lay the blame on me.他企图把责任推给我.
(文/刘宏清；英语辅导报高三版2003-2004学年第37期；版权归英语辅导报社所有,独家网络合作伙伴新浪教育,未经许可,不得以任何形式进行转载.)