CHANGCHUN, Oct. 21 (Xinhua)-Chinese train maker CRRC Changchun Railway Vehicles Co., Ltd. on Wednesday rolled out【小题1】 new type of high-speed train【小题2】 can run on different rail systems.

The train, with a standard speed of 400 km per hour, has been developed to cope【小题3】 different rail systems on international routes,【小题4】 (make) international rail travel more convenient.

The company said the train can operate in temperatures between minus 50 degrees Celsius【小题5】 50 degrees Celsius, and can also operate under different traction power supply systems and railway transportation standards of different countries.

【小题6】 (base) on the prototype and technology, the company is ready to take orders for customized high-speed trains and train products according to the technical standards and operational requirements of various regions of the world.

There are【小题7】 (current) four main railway track standards around the world. When ordinary trains run between countries with different gauges, they need to replace their train bogies, which takes time and effort.

As the new CRRC train【小题8】 (equip) with gauge-changing bogies, it can change【小题9】 (it) rail mode during cross-border travel, greatly improving the【小题10】 (efficient) of travel across rail systems.

The concept of the crossbow（弩） developed from animal traps.【小题1】is difficult to establish the date of the first development of the crossbow as a weapon. A scientist named E.M. Grosser discovered a bronze pistol（手枪）－like version 【小题2】 Robert Templel said could have been from the “eighth or ninth century BC or even 【小题3】（early）.” There are references to the crossbow in China in the sixth century BC. By the fourth century BC military leaders were relying【小题4】（strong）on crossbow—armed forces. One Han prince spoke in 336 BC of having 【小题5】（thousand） of crossbows for his army.

The crossbow had the advantage of not only 【小题6】（send） an arrow with enough force to cut through body armor（盔甲）【小题7】its arrows, being short, could not be shot back by bowmen. Over the decades the crossbow was improved upon. The trigger（触发）mechanisms were cast out of bronze and became as complicated as those of a modern gun. Rectangular frames（矩形框架）were attached to the front and back of the crossbow as sights 【小题8】（make） it easier to aim.

The strength of the bow on a crossbow made it difficult to prepare for firing. This device 【小题9】（enable） the bowman to hook the bow—string over the bow and use his legs to push against the bow. Later larger crossbows 【小题10】（build） to shoot multiple arrows at a time.

Driverless cars used to be the sort of thing you’d see in science fiction films--- 【小题1】 they are becoming a reality. Autonomous car technology is already 【小题2】 (develop) by the likes of Lexus, BMW and Mercedes, and we’ve even tested Tesla’s driverless cars on UK roads.

The Google Car is one of the most   【小题3】(experience) autonomous vehicles, and its interaction with human drivers 【小题4】(expose) one of driverless cars’ main weakness. The first injury   【小题5】 (involve) the Google Car wasn’t due to a fault in its system,but human error.

While 【小题6】 (correct) waiting at traffic lights, Google’s self driving car was hit by an inattentive driver and , 【小题7】 its advanced sensors, there was 【小题8】it could do to avoid the incident. Luckily, the accident only resulted in injury for a few of the passengers, but it’s a 【小题9】 (remind) that autonomous cars are at risk when   【小题10】 (surround) by human road users.