As we all know, the functions of our skin are very        .

 There was a _______ look on her face when she met with the _______ problem. 

He’s not got another job yet and it’s not ________ he will for some time. 

I should consider myself failing my duty if I didn’t take       action at that moment．

     in writing a lecture speech on AIDS prevention , she has no time to attend to her sick mother .