Alas , experience is a " lantern on the stern , which shines only on the waves behind us " .
唉，经验就是“一盏船尾的灯，它只照耀在我们身后的波涛上”。
Splitting water is one way to solve the basic problem of solar energy : it 's only available when the sun shines .
解裂水解决了利用太阳能的一个基本问题：它仅当太阳照耀时可用。
Air conditioning could be combined with solar power which has one obvious advantage , says maidment . " When the sun shines , you need air conditioning . "
空调可以结合太阳能-这至少有一个优点，梅德门特说“当阳光照耀时，你需要空调。”
It shines in the constellation of canis major and is visible from most everywhere in the northern hemisphere during the winter months . In the southern hemisphere , sirius is visible from all locations during their summer , north of the antarctic circle .
