Corrections in red.  Stylistics in blue.

The 30th Anniversary of Our Marriage. Please, make corrections.

My neighbor told me a story. One day he went to a jewelry store to buy a ring for his wife, because it was the 30th anniversary of their marriage.

He chose the ring which his wife wished for the most, but he didn't have enough money. He needed a little bit more in order to have 1,000 rubles. [1]  At that moment an owner showed up.

My neighbor wasn't taken aback, and asked the owner: "Could you give me a discount? It's the 30th anniversary of my marriage tomorow".

The owner asked him in return: "Have you ever cheated on your wife?" My neighbor was shocked and said, "I've never cheated on my wife. We have been happily living together for 30 years."

The owner answered, "Well, then I'll give you a 1,000 ruble discount". I guess, such good things happens sometimes.  The marriage bed could make some benefit. :)

[1]  Colloquial variant:  He needed a little bit more to make 1,000 rubles."    "to make" can mean "add up to."

A husband tells his friend, "My wife and I have lived together happily for 5 years."  His friend says, "Congratulations!"  The husband replies, "Don't congratulate me.  We've been married for <em>30</em> years."

The 30th Anniversary of Our Marriage.
 

My neighbor told me a story. One day he went to a jewelry store to buy a ring for his wife because it was the 30th anniversary of their marriage.

He chose the ring which his wife wished for the most, but he didn't have enough money. He needed a little bit more in order to have 1000 rubles. At that moment an owner showed up.

My neighbor wasn't taken aback and asked the owner: "Could you give me a discount? It's the 30th anniversary of my marriage tomorow".

The owner asked him in return: "Have you ever cheated on your wife?" My neighbor was shocked and said: "I've never cheated on my wife. We have been happily living together for 30 years".

The owner answered:"Well, then I'll give you a 1000 rubles discount". I guess such good things happen sometimes. The marriage bed could benefit :)