Imperfective and Perfective Russian Gerunds

Did you know that we have 2 types of gerunds in the Russian language, the imperfective and the perfective one? Imperfective gerunds are only formed from imperfective verbs with the use of the suffixes -а (-я) and the perfective gerunds are only formed from perfective verbs with the use of the suffixes -в (-вши, -ши, – вш, -учи). Imperfective gerunds mean additional simultaneous action (doing something) and perfective gerunds mean an additional finished action in the future or in the past that normally takes place before the main verb in the sentence.

For example,

1. Выходя из дома, он забыл взять зонтик. Leaving the house, he forgot his umbrella.
2. Выйдя из дома, он понял, что забыл зонтик. When he left the house, he understood that he had forgotten his umbrella.