【C6】A．UnlessB．IfC．ThoughD．As

【C15】A．UnlessB．IfC．BecauseD．Since

【C12】A．AsB．As ifC．ThoughD．Unless

【C6】A．instead ofB．as ifC．ahead ofD．except for

【C5】A．becauseB．ifC．thoughD．when

【C6】A．unlessB．ifC．asD．since

【C9】A．becauseB．ifC．thoughD．when