Over the centuries, English and Russian have expanded their vocabularies by borrowing words from different languages. For that reason, we have quite a few words that sound similar (or almost similar) in both languages. When you pronounce the Russian words компьютер or спорт, for example, you could easily guess their meanings without looking them up in the dictionary because there are similar words computer and sport in English. These types of words, called cognates (когна́ты), can contribute to vocabulary building immensely. In other words, they are your true friends in learning Russian.
Here are a few examples of true cognates.
However, there are some words that “pretend” to be true cognates. Even though, they sound similar, they do not have the meanings you expect them to have. They are called false cognates for that reason. In Russian, they are sometimes called ло́жные друзья́ перево́дчика, which literally means translator’s false friends. These words can trick you and sometimes create misunderstanding. You should be aware of these tricky false friends of yours.
Here is an anecdote (not a joke). One of my Russian friends brought her non-Russian speaking children to Russia to visit their grandparents. In a store, her nine-year-old son heard a Russian kid saying to his mother, “Mama, die, die, die!”. Thinking that a kid wanted his mother to die, he was shocked and terrified. My friend explained to her son that there is nothing horrifying in this situation: the child was just asking his mother to give him something.
The innocent Russian phrase «Мама, дай, дай, дай!» is nothing but the English “Mom, give me, give me, give me!” (“Дай” is the imperative from “дать” = to give).
The moral of the story: When you are not aware of false cognates, you could find yourself confused, misunderstood, frustrated, and even embarrassed. In order to avoid a situation like that, you should learn at least the most common ones.