合金渗碳钢渗碳后必须进行（）热处理才能使用。

If a boy or a girl has grown up in a home with sharing tasks and decisions，he or she will probably______.

29．__________ when you are on the bus or bike．

Either he or I ______to the airport.

Duty is an act or a course of action that people __________you to take by social customs, law or religion.

Duty is an act or a course of action that people ______you to take by social customs, law or religion.

Project ______is an uncertain event or condition that，if it occurs，has a positive or a negative effect on at least one project objective，such as time，cost，scope，or quality．

_____city do you prefer, Shanghai or London?

It will be a relief over the death of a friend or a relative if the friend or relative dies from ______.

Hurry up, or you ______ catch the train.

合金渗碳钢渗碳后必须进行（）后才能使用。

合金渗碳钢渗碳后必须进行（）热处理才能使用。