they confuse my brain.
"The old man thought that his son was calling to him"
I'm going with "senex putavit filium eum advocisse". Is that OK? Having two objects confuses it i think. Would "the old man thought that his son had called him" be better??
Also, when relative clauses appear things get confusing. eg. "The merchant replied that the slaves who were pouring out wine had been bought for a great price". I went ...