Answer:
He believes that before jumping to the conclusion that certain video games increase violent behavior in young people, it is necessary to study the effects for a longer period of time.
I assume you mean the three tenses, but let me know if you need more.
Past Tense: "Birds flew in the sky."
Future Tense: "Birds will fly in the sky."
The sentence is already in the present tense.
A verb is an action. Such as run, read, breath, etc
So, the verb in this sentence is "take"
