2 . Since 18^th January, 2018, some airlines in China __________ mobile phone use on their aircrafts.

6 . Much of today’s science of physics is based on Newton’s discovery of the three laws of motion (运动) and his theory of gravity (重力). Newton also developed one of the most powerful tools of mathematics.

Isaac Newton was born in Wools Thorpe, England, on Dec 25, 1642. He was born early. He was a small baby and very weak. No one expected him to survive. But he surprised everyone. Newton’s father died before he was born. The boy was not a good student. Yet he liked to make things, such as kites and clocks and simple machines. Newton also enjoyed finding new ways to answer questions or solve problems. As a boy, for example, he decided to find a way to measure the speed of the wind.

On a windy day, he measured how far he could jump with the wind at this back. Then he measured how far he could jump with the wind in his face. From the difference between the two jumps, he made his own measure of the strength of the wind.

It soon became clear, however, that the boy was not a good farmer. He spent his time solving mathematical problems, instead of taking care of the crops. He spent hours visiting a bookstore in the town, instead of selling his vegetables in the market. Newton became a student of Cambridge University.

The leading English poet of Newton’s time, Alexander Pope, honored the scientist with these words, “Nature and nature’s laws lay hid in night. God said, ‘Let Newton be!’ and all was light.”