The income of skilled workers went up. ________, unskilled workers saw their earnings fall.

To learn English well, we should find opportunities to hear English______ as much as we can.

 Teachers have to constantly update their knowledge in order to maintain their professional ________.(2011·江苏，27)

Mary worked here as a ____ secretary and ended up getting a full-time job with the company.

With so much water being used in the bathroom,it is no  _____ that more   environmentally friendly technologies have come out to make better use of water resources.