Say what could or might happen
To say something could happen, use podría (conditional of poder) + infinitive.
Podríamos ir al cine. (We could go to the cinema.)
¿Podrías ayudarme? (Could you help me?) — polite request
Forms: podría, podrías, podría, podríamos, podríais, podrían.
Puede (present of poder) + infinitive expresses ability or real possibility.
Puede llover esta tarde. (It may rain this afternoon.)
Puedo llegar a las seis. (I can arrive at six.)
Quizás and tal vez both mean "perhaps / maybe". At A2, use them with the normal indicative.
Quizás voy mañana. (Maybe I will go tomorrow.)
Tal vez está en casa. (Perhaps he is at home.)
You will later meet these with the subjunctive (quizás vaya) — both are heard in Spain.
A lo mejor is the most colloquial option — and good news: it always takes the plain indicative.
A lo mejor vamos a la playa. (Maybe we will go to the beach.)
A lo mejor es verdad. (Maybe it is true.)
You will also hear es posible que + subjunctive. Recognise it at A2; you do not need to produce it yet.
Es posible que llueva. (It is possible that it will rain.)
Traps for English speakers
These are the errors English speakers make most often.