例句 1:She placed the letter carefully inside the envelope.
例句 2:He handed me a sealed envelope and asked me not to open it until tomorrow.
例句 3:The job offer came in a plain white envelope.
例句 4:Please write your return address on the back of the envelope.
例句 5:The envelope was marked “Confidential” in red ink.
例句 6:We’re pushing the envelope with this new design—it’s bold and innovative.
例句 7:Don’t forget to put a stamp on the envelope before mailing it.
例句 8:The budget envelope for this project has already been exceeded.