1. I could speak English a year ago2. All the students must read this text again3. You may keep this book4. His parents can help him with his studiesЗмінити речення вживаючи мовні дієслова​

1. Are you waiting for the bus at the moment? Здесь используется Present continuous, потому что есть указатель времени - at the moment 
2. It snows every winter in my country. Используется Present Simple, потому что EVERY WINTER - действие повторяющееся, каждый год, каждую зиму.
3.  What is he doing now? - NOW - указатель на Present Continuous.
4. How many Noble Prize winner there had been? - Здесь уже Past Perfect
5. ??? 
6. Have you been at school yesterday? - yesterday указывает на Present Perfect

Hi, my dear friend, how are you? Now I want tell you about my holidays. I went from my town with parents on this holidays! I'm very happy from this, because fe have many fun. We saw mountain river, it was so fast and because of this we didn't swim there. And else we was on the picknik. Father and mother was very happy. Then we played basketball together, me and mum versus dad. It wasn't winner. When we came home, we have long tea Party with chatting about holidays. But I was upset, than you didn't go with us. I want see you with us next holidays, we'll have many fun!Your friend, Vlad.