TV picks for April 21:  Sophia Loren, "The National Mall," "Taxi"

"The National Mall: America's Front Yard" takes viewers on a shopping spree through our beloved institution, stopping at some of our favorite stores and — what's that? There's another Mall, one that features something called the Lincoln Memorial? Huh. Learn something every day. 7 p.m. Tuesday, TPT, Ch. 2

Legendary actress Sophia Loren doesn't do much acting these days, which is why we're curious about 2013's "Human Voice," directed by her son Edoardo Ponti. That's followed by four of Loren's earlier classics. What, no "Grumpier Old Men"? 7 p.m. TCM

For a long time, it was almost impossible to find reruns of "Taxi," the best network sitcom of its time. Fortunately, we can now enjoy episodes on MeTV. The latest offering is one of the best, a one-hour episode in which all of the characters flash back to moments that changed their lives. 9 p.m. MeTV

Neal Justin