Both и and а may be translated into English like and. The difference is that и is uniting words or sentences, whilst а is opposing them:
Olya and Sveta are going to the cinema.
Оля и Света идут в кино.
Olya is going to the cinema and Sveta is going to the concert.
Оля идет в кино, а Света — на концерт.
(We usually omit the repetitive verb and put a dash instead, though writing it another time would not be a mistake: Оля идет в кино, а Света идет на концерт.)
How are you? – I’m fine and you?
Как дела? – Хорошо, а у тебя?
I buy food and clothes.
Я покупаю продукты и одежду.
I buy food and you buy clothes.
Я покупаю еду, а ты покупаешь одежду.
Preposition с means with. The noun following this preposition is always in Instrumental case (lesson about cases).
With my friend – с другом
With my brother – с братом
When you use with to express the means of doing something, the noun will be also in Instrumental case, although you don’t put the с in the Russian translation. For example,
I open the jar with the knife.
Я открываю банку __ ножом. – No с needed.
The preposition с also may be translated as and but the noun will stil be in Instrumental case:
My friends and I are going to the mountains.
Я собираюсь в горы с друзьями.
Now let’s practice. Write the missing word. First try to put them without listening to the audio.
1. What are you doing today? – Что ты сегодня делаешь?
I am getting rest with my family. – Я отдыхаю ___ семьей.
2. Masha and Andrey are going to the restaurant. – Маша ___ Андреем идут в ресторан.
And you? – ___ ты?
I am eating with my sister tonight. – ___ я сегодня ужинаю ___ сестрой.
3. Today I’m going to the store and cleaning up the apartment. – Сегодня я иду в магазин ___ прибираю в квартире.
Vocabulary from this lesson:
to buy – покупать
food – продукты (when we talk about buying food; sing. продукт)
clothes – одежда
knife – нож
jar – банка
to be going to – собираться
getting rest – отдыхать
family – семья
to eat – ужинать (to have dinner)
cleaning up – прибирать
apartment – квартира