seal

邮寄前请密封信封。

Please ___seal the envelope before mailing it.

他用湿海绵安全地密封了包裹。

He used a wet sponge to ___seal the parcel securely.

我们能看到一只海豹在岩石海岸附近游泳。

We could see a ___seal swimming near the rocky shore.