选词填空，将方框中单词的合适形式填在横线上。
Dogs are ___________( 诚实的 )friends of human beings. 
I felt so happy because my father ____  _ ( 答应 ) to buy me a new cellphone.
Please tell me the____________（原因）why you are late.
Would you give me some bread? I am so ___________( 饥饿  ) .
Who can give this question a  ________（正确的）answer?