单项选择题 Because of recent political and economic upheavals in these countries, it seems likely that the trend will be toward decentralized, Western-style systems.
单项选择题 As we can no longer wait for the delivery of our order, we have to ______ it.
单项选择题 Mercury orbits the Sun in 88 Earth days at an average speed of 48 kilometres per second, allowing it to overtake Earth every 116 Earth days.