Assume the statements are true.

Statements: Some sails are flags. No flag is a banner.

Conclusions:

I. All sails being flags is a possibility.

II. Some banners being sails is a possibility.

Explanation

1. 01

   Draw the sail circle entirely inside the flag circle. It still overlaps flags and no flag is a banner, so every statement holds: I follows.

2. 02

   Or let some sails lie outside the flags and overlap the banners. The statements still hold, so II follows.

3. 03

   Both I and II follow.