Is this sentence right grammatically?

Right, "for" does not work in that context.

"within 7 days" includes the possibility that it might be finished earlier, whereas "in 7 days" does not (at least, not so obviously).

If you want "for", change the verb:

The study will continue for another week (7 days.).

For 7 days = I had a high fever for 7 days. We will pack for 7 days in May to Europe.

will be finished does not suggest duration, will be finished after, will be finished in, will be finished before, generally will be finished around at a specific point in time

The study will require the entire team for 7 days.
The study will be fi

tntenglishmasterIs this sentence right grammatically?
The study will be finished for 7 days.

No. 'finished' takes place at a point in time. 'for seven days' takes place over a period of time.

That's a contradiction. 'in seven days' is what you want.

CJ

@AlpheccaStars I think the sentence should be in the passive voice. "The study will be continued (by me) for another week" Is this wrong?

vkr6078@AlpheccaStars I think the sentence should be in the passive voice. "The study will be continued (by me) for another week" Is this wrong?

The active voice is the most common use.
The passive sounds a bit odd, though it's not wrong.

Grammatically, how can "study" can continue "itself" for another week? It can be continued or finished only by me. Sometimes, I get confused with passive and active voice.

See the definition of continue: http://dictionary.reference.com/browse/continue?s=t

The verb has both transitive and intransitive forms.
Only transitive forms take an object and can be changed from active voice to passive voice:

Intransitive:
The program continued after an int

What about this sentence "If you leave the motor in the ON position for days, it will get damaged/will damage."

"will get damaged" or "will damage"? Why is "get damaged" correct but not the other one?

'Damage' is used only transitively.