Take care! _______ to frequent smog does great harm to your health.
| A．Exposing | B．To expose |
| C．Exposed | D．Being exposed |
Yang Liwei，China’s first spaceman，prepared carefully for going to space so that he could be sure of success at his first _________.
| A．experiment | B．flight |
| C．attempt | D．try |
Seeing the happy_________of children playing together there，I’m full of joy and hope for the future of our country.
| A．scene | B．sign | C．sense | D．view |
In the after-class activities，the students had plenty of_________and gained a lot of practical _________.
| A．experience;experiences |
| B．practices;experience |
| C．practice;experience |
| D．exercise;knowledges |
Jason has been preparing carefully for his English examination so that he could be sure of passing it at his first_________ .
| A．purpose | B．desire |
| C．attempt | D．intention |
She is always ready to help people in trouble because she thinks it is a_________ .
| A．business | B．reward |
| C．pleasure | D．favor |