下午四点半放学用英语怎么说

"School lets out at 4:30 PM" is the English equivalent of "下午四点半放学".

This phrase is commonly used to express the end time of a school day in English speaking countries.

Here are some example sentences in English with Chinese translations:

"What time does school let out today?" (今天放学几点?)
"School lets out at 4:30 PM, so I need to leave work early to pick up my kids." (放学时间是下午4点半，所以我需要早点离开工作来接孩子。)
"I can't wait for school to let out, it's been a long day." (我等不及放学了，今天真的太长了。)

Note: The use of "let out" here is a colloquial expression, meaning "to end" or "to finish".