When Do I Use the Subjunctive?

The subjunctive mood in Spanish should be used when opinions, wishes and emotions are expressed and for phrases that convey a possibility or doubt. For example, phrases such as 'no creo que..', and 'es probable que..' would trigger the subjunctive, (however, 'creo que' or 'es obvio que' would not as they are not statements of possibility or doubt but are facts or expressions of belief.) In order to remember this, it would be useful to use the acronym 'WEIRDO'- Wishes, Emotions, Impersonal Expressions, Recommendations and Doubt, (also denial, ) and Ojalá, (an expression of wishing for something.) For example, the phrase 'Espero que pases tus exámenes' (I hope that you pass your exams,) would trigger the subjunctive as it expresses an emotion/wish. Which of the examples below requires a subjunctive? Highlight the correct conjugation.

Es posible que llega/llegue tarde. No creo que puedo/pueda caminar tan lejos. Pienso que estás/estés cansado.