(2013·辽宁六校高三联考)After walking on the zigzag path to the mountain top for a few hours, the tourists gathered under trees ________ shade and ________ down to have a rest.

The matter_______ people’s health surely requires________ carefully.

More highways have been built in China,___________it much easier for people to trave form one place to another.                            

 She didn’t feel happy_____ in a block of apartments. She’d rather ______ in a traditional house.

The education program ________ combining brain work with manual labor is being widely spread throughout the country.