In many volcanoes the lava bubbles quietly, tossing lava into the air at times, giving off gases, and, in general, being fairly harmless . 许多火山的熔岩静静地在冒泡，有时喷入空中，释放出气体，一般是完全无害的。
When a solution of chlorophyll is placed in a beam of white light, it gives off light of a deep red hue. this phenomenon is called fluorescence . 当叶绿素溶液置于白光光柱中，溶液发出暗红色的光，这一现象称为荧光现象。
These rotting bananas are giving off a bad smell 这些腐烂的香蕉发出难闻的气味
When wine is fermented , it gives off bubbles of gas 当酒已经发酵时它会发出气泡。
This fire doesn ' t seem to be giving off much heat 这火似乎不太能散发出热。
Heat and light can be given off by this chemical change 这种化学反应能放出热和光。
A metal called uranium gave off a kind of radiation 一种叫铀的金属会发出一种射线。
The boy ' s dirty shirt gave off an unpleasant smell 这男孩的脏衬衫散发出难闻的气味。
At 60 mpg , they would give off a billion tons 如果是每公升25 . 2公里，就会排出10亿吨。
When wine is fermented it gives off bubbles of gas 酒发酵时会放出气泡。
