He pressed down on the sack and it went under water.

他使劲一按，袋子沉进水里了。

But later, there must have been darkness; complete darkness and silence, as the summer fog pressed down on the water.

但后来，一定有黑暗； 完全的黑暗和寂静， 夏日的雾压在水面上。

Sometimes the animal pressed down on the chip and breathed in, suspending the chip on the tip of trunk without breaking it.

有时动物会压住芯片并吸气，使芯片悬在树干的尖端而不致折断。