A giant ship appeared in Tokyo, and three years have passed. The daily routine seemed to have ended, and the world appeared to be on the brink of destruction. However, the ship did nothing, and life continued as usual. 
you’d get good grades on the mock entrance exams, 
then do badly on the in-school tests.
so ein Unterschied, nur weil du
sie hier schreiben musst, ist ungewöhnlich.
Странно, что только
на серьёзных тестах валишься.