Radioactivity is the ejection of particles or radiation from the nucleus.放射性是原子从核中射出粒子或辐射的现象.Most of the crater is formed by ejection.大多数的弹坑是由于把泥土抛出而形成的.A rocket is propelled by the ejection of a portion of its mass to t...
他们打开金库, 拿走两袋钱,里面装有二十七万九千美元.They opened the vault, removed the two money bags containing $ 279,000.他走后我把信封打开,里面有1000美元的捐款.After he left opened the envelope and found it contained a $ 1,000 contribution....