Here’s a quick sketch of Canada House on Trafalgar Square, seen though the modern windows of the National Gallery Sainsbury wing.

While I sketched, I overheard fragments of conversations: “I was dating a Chinese girl, and she was taller than me…..”, and someone on a mobile phone: “It needs to be connected to the WiFi…yes…though why one would want the dishwasher… I don’t know!”
About 30mins pen and ink on location, colour added later.