Стюардесса вышла из кабины пилота по всему самолету и вернулась обратно. Чему приблизительно равен путь стюардессы

1) When have students vacations?
Twice a year students haven't vacations.
2) Which subjects do students study the first-year?
The first-year students not study general engineering subjects.
3) Will the Dean send the students to a big plant in summer?
The Dean won't send the students to a big plant in summer.