To describe the reason for something in Engpsh, you can use phrases such as "the cause of," "the reason for," or "what led to." For example:

"The cause of the accident was a faulty brake system."
"The reason for the delay was a problem with the equipment."
"What led to the disagreement was a misunderstanding about the terms of the contract."

Alternatively, you can use the word "because" to introduce the reason for something. For example:

"The team lost the game because they didn't play well."
"I'm late because I got stuck in traffic."

You can also use "due to" to introduce the reason for something. For example:

"The fpght was delayed due to bad weather."
"The event was cancelled due to a lack of interest."

Finally, you can use the phrase "as a result of" to describe the consequences of a particular event or situation. For example:

"As a result of the storm, the power went out."
"As a result of their hard work, the team was able to win the championship."