Five or six words is a huge amount of entropy. In reality there are other rules in my example than just using words. It starts with a capital letter and includes a conjugated verb (running) both of which increase complexity considerably. And it of a random length, having taken its length from my selection of words rather than from any fixed policy. Few services accept random lengths but imho all should.

There is a great scene in DoctorWho where a door password is a series of concepts (spoken mentally) that one thinks about in a particular order. Fiction, but the person writing that scene knew a thing or two about password complexity.