Cool, Refreshing
い adjective
This is a single kanji with an い on the end, meaning you know it's probably an adjective. What's the adjective form of cool? It's cool. 涼しい is used to describe a comfortable level of coolness, particularly one that's pleasant and refreshing.
すずしい
The reading is the kun'yomi reading, but that's the reading you learned with the kanji so you should be able to read this one too. If you need a refresher, here's a mnemonic to help you: Looking for a place that's cool and refreshing? Go to the Sue Zoo (すず). Imagine swimming with Sue the penguin in the refreshing water of her pool. Feels good!
今日はとても涼しいですね。
It is very cool today, isn’t it?
いいね、そのドレス。涼しそう。
I like that dress. Looks breezy.
涼しい顔でよくそんなこと言えるね。。
How can you say such a thing with an indifferent face?