Сделайте "хвостик": 1) they were happy to get the invitation letter, ? 2) yesterday your friends went to the cinema, 3) the group of students won`t stay in the hotel, 4) his collection of stamps was the best, 5) the head teacher didn`t write the letter, 6) we can arrange a date and time right now, если можно, переведите.
didn't they
will they
wasn't it
did he
can't we