Instruction
1
A gerund always consists of a participle and its dependent words. Communion is a special verbal form with an adjective (adjective). Adjectival characteristics of the participle: gender, number, case, full or short form - they can change. Verbal signs of the sacrament: manage, view, the Deposit (divided into active and passive participles) and time. These symptoms are constant. Consider the examples:

Offender robbed a Bank, escaped prosecution of the police.

Define the word "criminal." "Robbed a Bank" is a gerund, where "robbed" is a valid sacrament, a "Bank" is a dependent word.

The amount of money stolen yesterday from the Bank exceeded $ 1,000,000.

Define the word "amount". "Stolen yesterday from the Bank" - a gerund, where "kidnapped" is an adjective, and "yesterday" and "from Bank" is the dependent word.
2
A gerund can stand before the modified word:

Tied up outside a shop dog barked loudly.

"Tied up outside a shop" is a gerund. In this case, it will not stand out with a comma.

If a gerund comes after the defined words:

A dog tied outside a shop, barked at a passerby.

The turnover will be allocated by commas on both sides.
3
In Russian language the sacrament came from old Slavic, so firmly taken root in the written word. Gerund is also a form of the verb preserved in the language since ancient times, but it has signs of dialect. To confuse the communion, answering the question "what?", with the adverbial participle, answering the question "how?" it is absolutely impossible, if you understand the rules above. By the way, "above" is also a gerund!