distend

气球被充气后逐渐膨胀起来。

The balloon began to ___distend as it was filled with air.

那条蟒蛇吞下整只小羚羊之后，腹部明显鼓胀起来。

The python's midsection visibly ___distended after it swallowed the small antelope whole.

腹部手术后四小时之内，病人的小腹迅速肿胀起来。

The patient's lower abdomen ___distended rapidly in the four hours after abdominal surgery.