Given the task definition and input, reply with output. In this task, you are given a paragraph, and your job is to generate comma-separated entities present in the given paragraph. Generate entities from a given passage in such a way that (i) they are present in the paragraph, (ii) they are non-duplicate, (iii) they underwent a state change during the process. Avoid creating entities that (i) aren't present in the process paragraph and (ii) aren't significant.

Water vapor is in warm air. The warm air cools. The warm air expands. The water vapor in the air condenses. The water vapor forms water droplets or ice crystals.
water vapor ,water droplets; ice crystals