@SMickey,
SMickey wrote:
2. Intellectuals tend to think than act.
I guess the one who wrote that sentence might have wanted to say,
Intellectuals tend to just sit tight and think, rather than stand up and take action.
In terms of grammar, is it completely fine to say,
'Intellectuals tend to think than act'?
there are a few possibilities here
to begin with - the sentence as presented is not correct.
The author might have left a word out, meaning to say something like Intellectuals tend to think rather than act.
Or it could have been a typo, with the sentence being Intellectuals tend to think, then act. If that was the intention, the sentence needs a comma or to be rephrased.
Intellectuals tend to think before acting.
Intellectuals tend to think before they act.
You'd have to know the intended meaning before correcting the sentence.