Как правильно сказать по " ты в 7 классе, не так ли? " и "ты учишься в 4 классе, не правда ли? "

"You in the 7th class, isn't it?" and "You study in the 4th class, isn't that so?"

You're in 7th grade, aren't you?

You study in 4th grade, aren't you?