【C18】A．BecauseB．IfC．AlthoughD．Unless

【C13】A．WhenB．SinceC．AlthoughD．Unless

【C16】A．becauseB．even ifC．sinceD．if

【C18】A．becauseB．whileC．whenD．if

【C12】A．becauseB．whileC．althoughD．so

【C12】A．AsB．As ifC．ThoughD．Unless

【C5】A．becauseB．ifC．thoughD．when