envelope

"My sister put the letter in an envelope and took it to the mailbox. "

"The letter was carefully placed inside the envelope. "

"The hot air balloonist carefully inspected the envelope for any tears before filling it with hot air. "

"The engineer used the envelope of possible flight paths to determine the safest trajectory for the rocket. "

"The technician carefully measured the envelope of the radio signal to ensure proper transmission. "

"The musician carefully shaped the sound of the trumpet using a synthesizer to create a specific envelope. "

"The envelope on the letter contained the address, but not the actual letter itself. "

"The onion's outer layer is a tough envelope protecting the delicate inner parts. "

"The new software program has a narrow envelope of acceptable temperatures for optimal performance. "

"The comet's envelope was a bright, fuzzy cloud of gas and dust. "

"The soldiers built an envelope around the village to protect it from enemy attack. "

"The thick cardboard box enveloped the fragile glassware, protecting it from damage during shipping. "