Две материальные точки движутся по окружностям радиусами R1=R и R2=3R с одинаковой угловой скоростью.Отношение модулей центростремительных (нормальных) ускорений a2/a1 равно

a)Match the words to make phrases.
to enjoy               guests
to take                abroad
to invite               place
to collect             the date
to arrange            badges
to go                   the film
b)Complete the sentences with the new word combinations.
1.Sam is gouing to ______ _______to his birthday party.
2.Lets _______ _______of the meeting.
3.Where will the party _______ _______?-In school.
4.Have you got any hobbies&-Yes,I _______ _______.
5.The head teacher got an invitation  letter yesterday.His students will _______ _______next month.