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31.All parents are willing to risk ________ their lives to save ________ of their children when a disaster is approaching.
| A．losing; that | B．to lose; those | C．losing; those | D．having lost; the ones |
As long as the laws of nature ______, there will be tornadoes.
| A．exist | B．are existing | C．will exist | D．existed |
North Korea fired a long-range rocket last month, but the launch was reported ______ in failure.
| A．to end | B．to have ended | C．having ended | D．ending |
Some scientists have questioned the theory ______ CO2 is causing dangerous global warming.
| A．which | B．what | C．that | D．why |
They studied what ______ since 2007 and found Australian electricity prices were among the highest in the developed world.
| A．has happened | B．happened | C．had happened | D．has been happening |
It's not how much money you make or who your daddy is ______ makes you the most attractive person in the world but the way you do some simple things.
| A．that | B．which | C．what | D．who |