In addition to previous comments ...
Most good interviewers want you to answer three key questions ...
1. Can you do the job? Do you have education, skills, experience ...
2. Are you motivated, do you want this job? You need to come across energetic and enthusiastic, etc.
3. Will we be able to tolerate you :-) ? Are you a team player, are you responsible, trustworthy, etc.
They will not ask the above directly, but will get the ianswers through other questions.
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Another thing, use as many examples from your school or previous jobs. There are always questions along the lines of - can you tell me how you would handle situation X?
A great way to answer that question would be to say - As a matter of fact I came across a situation like this when working for ABC company.
1. Here is exactly what happened.
2. Here is what I / my team did.
3. Here is the result / outcome
4. Here is what I have learned.
Be brief and to the point.