The outer envelope of HIV is covered in glycoproteins which mutate frequently, ultimately tricking the T-cell receptors to not recognize the virus.

艾滋病毒的外包膜覆盖着糖蛋白最终唬弄过T细胞的感受器以致无法辨认出病毒。

In five billion years, the Sun will explode and throw off its outer envelope.

五十一億年後，太陽爆炸並將外層拋出後。

In five billion years, the Sun will explode and throw off its outer envelope, leaving at the centre of the Solar System, a gradually cooling stellar core.

五十亿年后，太阳将爆炸并脱离它的外层，在太阳系的中心留下一个逐渐冷却的恒星核心。