70 σφόδρῶς states, “very much, greatly, violently … σφ. χειμάζεσθαι be violently beaten by a storm Ac 27:18.”
71 Or “jettisoning [the cargo]” (a nautical technical term). The words “the cargo” are not in the Greek text but are implied. Direct objects were often omitted in Greek when clear from the context, but must be supplied for the modern English reader. The desperation of the sailors in throwing the cargo overboard is reminiscent of Jonah 1:5. At this point they were only concerned with saving themselves.

In other versions

Since we were violently storm-tossed, they began the next day to jettison the cargo.

We took such a violent battering from the storm that the next day they began to throw the cargo overboard.

Because we were being severely battered by the storm, they began to jettison the cargo the next day.

The next day, as gale-force winds continued to batter the ship, the crew began throwing the cargo overboard.

And because we were violently battered by the storm, on the next day they began jettisoning the cargo,

And we being exceedingly tossed with a tempest, the next day they lightened the ship;

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