完成句子。（每空一词）
They bought a house in 2012.（改为同义句）
They______  _______a house since 2012.
We ought to be polite to the old.(变否定句）
We______  _______be polite to the old.
There is something delicious on the table.（改为一般疑问句）
______  there ________ delicious on the table?
尽管他很富有，他仍然过着简朴的生活。
______   _______he is rich, he lives a simple life.