verb
to close packaging (= material used to wrap or protect goods) so that the contents cannot get out封闭 ◆ Heat is applied to seal the shrink-wrap. 热缩塑料薄膜包装需要加热来封口。
to close an envelope by sticking the edges of the opening together 封上（信封） ◆ Make sure you've signed the form before sealing the envelope. 确保在封上信封之前你已经在表格上签了名。
to make sth definite and final, so that it cannot be changed or argued about 使成定局 ◆ They hope to seal the deal with a cash offer of €35 per share. 他们希望以每股 35 欧元的现金出价敲定这笔交易。
