[Jim Noble]

he may, on extraordinary Occasions, convene both Houses, or either of them, and in Case of Disagreement between them, with Respect to the Time of Adjournment, he may adjourn them to such Time as he shall think proper

Have the Senate vote to adjourn, the House will disagree, and Trump can adjourn Congress until December 31, 2020.

[Publius]

Adjournment is not recess. If the Senate adjourns, it does so for the remainder of its legal term of office. It cannot be called back into session unless the president calls a special session of Congress. However, adjournment of the Senate requires a unanimous resolution. (”Without objection, it is so ordered.”) That will never happen.