Помогите, пожалуйста.ничего не могу понять. when 2 boys found the skeleton of kennewick man in 1995 it _____(think/be) the remains of a murdered man,but____(later/discover/be)over 9000 years old.
It had been thought the remains of a murdered man later was discovered...
later were discovered
можно объяснить, пожалуйста, почему had been?
But have been кажись