What should the Democrat's do with their house majority?

From the economist:
"The main onus is now on the Democrats. For their own good, not to mention the country’s, they have to find ways to appeal in America’s heartland.

That starts with exercising restraint. Yes, they should use their majority in the House to scrutinise a president who shows contempt for the norms that have constrained past presidents. They should look carefully at what has been going on in federal agencies, and investigate possible presidential abuses of power or misuse of the office for personal aggrandisement. But Democrats should resist the urge to use their majority in the House to take revenge, hounding the president in the way that Newt Gingrich and his Republican colleagues once hounded Bill Clinton. Prosecution should be left to prosecutors."
https://www.economist.com/leaders/2018/11/08/the-mid-terms-produce-a-divided-government-for-a-divided-country