Grandpa is familiar with the art of war, but he knows nothing about the past. Every time I play chess with my grandson, he loses. What tactics does grandpa use?

If it is true, then this grandfather is cultivating his grandson's interest in chess. If an old man is not good at playing chess, he is not so good that even his grandson can play chess. Will he still be happy to play with his grandchildren often? (The word "every time" in the landlord's sentence means to go down often)

Generally speaking, when a person does something well and gets more praise, he will be happy to do it. The same is true of grandson playing chess, and grandpa understands this truth.

It is not a tactic, but it is more appropriate to describe wisdom as stupidity.