All of these reporting verbs are a variation on the verb to think. They all refer to people's thoughts, rather than to what they say. They can be used to refer to different types of thoughts ...
In English, our sentences usually operate using a similar pattern: subject, verb, then object. The nice part about this type of structure is that it lets your reader easily know who is doing the ...
However, there are many types of noun and noun phrase in English, and it can be difficult to know if a particular noun takes a singular verb (such as DOES / HAS / AM / IS ) or a plural verb (DO ...