Use of subjunctive form?

Question

I know that when you introduce a statement with 'if,' you are speaking in the subjunctive and therefore use 'were' instead of 'was' (e.g., "If I were to do this thing, something else would happen.").And the same is true if a statement is introduced with 'wish' (e.g., "I wish it were warmer."). As it is if you begin with 'as though' (e.g, "He said, as though it were cold."). But it doesn't seem appropriate to use 'were' in all cases of uncertainty (e.g., you wouldn't say "I thought it were cold."). Does saying you thought something was the case simply not qualify as an uncertainty, meaning you shouldn't use the subjunctive? Or is there some subtler logic behind when the subjunctive form is used in English?

Answer 1

The noun clause which is the object of the verb "think" is always in the indicative mood--never in the subjunctive. It's just a rule regardless of the uncertainty expressed. Though, I do believe, in Old English, a sentence like "I thought it were cold" may have been acceptable (in the subjunctive). Try saying it in a Scottish accent; for some reason, it feels almost right. :)