英语中表达多大了怎么说

To express "how old" in Engpsh, you can use the phrase "how old are you?" or "what is your age?" If you want to express the age of someone or something else, you can use the phrase "how old is (name/it)?" For example:

"How old are you?" (to ask someone's age)
"What is your age?" (to ask someone's age)
"How old is your sister?" (to ask the age of someone else)
"How old is this building?" (to ask the age of something)

Alternatively, you can use the word "old" to describe the age of someone or something. For example:

"He is an old man." (to describe someone's age)
"This car is old." (to describe the age of something)