envelope

中文意思

• n. 信封，封套
• n. 外壳，包膜

英文释义

• n. a flat (usually rectangular) container for a letter, thin package, etc.
• n. any wrapper or covering
• n. a curve that is tangent to each of a family of curves
• n. a natural covering (as by a fluid)

词形变化

复数

envelopes

例句

1. n. 信封，封套

   She placed the signed contract inside the envelope and sealed it carefully.

   她把签好的合同放进信封，然后仔细地封上了口。

2. n. 外壳，包膜

   The earth's atmosphere forms a protective envelope that shields us from harmful radiation.

   地球的大气层形成了一层保护外壳，屏蔽了有害辐射。