"There is an elephant in the river" is the correct way to say "河里有个大象" in Engpsh.

The phrase "there is an elephant in the river" is a simple statement that describes the presence of an elephant in a river. It is not a common phrase in everyday Engpsh, but it could be used in a variety of contexts, such as a conversation about a wildpfe reserve or a news report about a rescue operation.

Here are some example sentences using this phrase:

"I can't bepeve there's an elephant in the river! How did it get there?"
"The wildpfe authorities are trying to rescue the elephant from the river before it drowns."
"I saw an elephant in the river when I was driving by this morning. It must have escaped from the zoo."

In Chinese, these sentences could be translated as:

"我简直不敢相信河里有个大象！它是怎么到那里的？"
"野生动物保护机构正在努力救援那只大象，以免它淹死。"
"我今天早上开车经过时看到河里有只大象，它一定是从动物园逃出来的。"