英文环保标示牌的内容可以多种多样，主要目的是提醒人们保护环境、珍惜资源。以下是一些常见的英文环保标语：
Keep the environment clean, so it will stay green.
Keep our nature healthy, cause it will make us wealthy.
Reduce wastes and recycle them instead, put them with plants and they will be fed.
Global warming is so uncool!
Save our precious Earth!
The Earth is in our hands.
Think green, keep it clean.
Love the Earth as you would love yourself.
Plant a tree and you plant a hope.
Respect nature, it's our only home.
这些标语简洁明了，易于理解和记忆，能够有效传达环保的重要性。你可以根据具体场景选择合适的标语，将其制作成环保标示牌，挂在显眼的位置，提醒人们时刻关注环境保护。
