Three guys standing by a tank. I’m pretty sure that none of them are Grandad.
After some not very thorough research, I’d say that the tank is a Medium Mark C ‘Hornet’ – which Wikipedia points out ‘was a British tank developed during the First World War, but produced too late to see any fighting’. Much like Grandad I’m pleased to say.
Grandad knew T.E. Lawrence (of Arabia) who had changed his name to T. E. Shaw and joined the Royal Tank Corps in 1923 apparently.