Statements: All fruits are vegetables. All pens are vegetables. All vegetables are rains. Conclusions:  All fruits are rains. All pens are rains. Some rains are vegetables.

III is the converse of the third premise and so it holds.

All fruits are vegetables. All vegetables are rains.

The conclusion must be universal affirmative and should not contain the middle term.

So, it follows that 'All fruits are rains'. Thus, I follows.

All pens are vegetables. All vegetables are rains.

Clearly, it follows that 'All pens are rains'. Thus, II follows.