It is ten years since the scientist ______ on his life’s work of discovering the valuable chemical.
| A．made for | B．set out | C．took off | D．turned up |
______ the danger ahead on the railway line, he decided to go to Beijing by plane instead.
| A．Having been informed of | B．Having informed of |
| C．To be informed of | D．Informing of |
My parents, without ______ help I wouldn’t have become who I am, have taught me the true meaning of life.
| A．whom | B．their | C．whose | D．them |
_ properly, a car can be used for many years.
| A．Maintained | B．Maintaining |
| C．To be maintained | D．To maintain |
______ is conveyed here to children is that reading is one of life’s greatest treats.
| A．As | B．What | C．That | D．It |
It is not until midnight ______ he goes to bed every day.
| A．before | B．when | C．since | D．that |