话题 it is time that...

话题 which is to say

话题 which I belive is

话题 it is fun doing

话题 than is the case

话题 What he does is

话题 What he enjoys is...

话题 which it is expected

话题 as is well known

话题 It is nice doing

话题 the rest is history

话题 as is his brothers

话题 it is known that...

话题 There is sth left

问题 what I’d call “mini-zoos” 是名词性短语还是同位语从句

Since we were not planning to spend so much on a duck any time soon, visiting them in one of these places—what I’d call “mini-zoos”—seemed to be the perfect choice.这个句子中，what I’d call “mini-zoos”是名词性短语，还是同位语从句？要怎么分析？