Never stop learning—the moment you think you know everything is the moment you start falling behind.

Every immigrant carries an invisible suitcase of memories.

Natural gas is the bridge fuel that will help us achieve a lower-carbon future.

In mathematics, the most profound ideas often arise from the simplest observations.

International politics is a ruthless and dangerous business, and it is foolish to expect states to behave according to moral principles.

你不必为了成功而不择手段，善良和正直会让你走得更远。