The reason for making a decision is that a problem exists, or something is standing ______the way of accomplishing them.

These natural resources will be______sooner or later if the present rate of exploitation continues.

A sound which is capable of distinguishing one word or one shape of a word from another in a language is a__________．

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.

______ is the address of a variable or a variable in which the address of another variable is stored.

______is the address of.a variable or a variable in which the address of another variable is stored.

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．

It is generally considered unwise to give a child___( )_____ he or she wants.

 ______ twice a year, whether it is a car or a bus or a truck, is the rule that every driver must obey in this city.

All ______ is a continuous supply of the basic necessities of life.( )

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