The two triangles coincide.这两个三角形相重合.The time - like limIt'surface, the apparent horizon and the event horizon no longer coincide each other.这种黑洞的事件视界 、 表观视界和类时极限面均不再重合.The kids' views on life don't always...
但在其他商店纷纷关门倒闭之时，大型超市的强劲扩张势头却依旧不减。But as other shops fold, the march of the superstores continues.积极扩张的市场经济是发展的必要条件。An active and expansive market economy is a necessary condition for progress.这个不断扩张的城市容纳了约400万人口。The spraw...
牙斑如果不清除就会导致牙齿蛀蚀和牙龈疾病。When not removed, plaque causes tooth decay and gum disease.牙齿和牙龈之间会滋生牙斑。Deposits of plaque build up between the tooth and the gum.需刷牙以去除牙斑.It is necessary to remove plaque by brushing one's tee...