Maybe

pode ser

(as a pro-sentence)

porventura

(indicating a lack of certainty)

porventura

(as a pro-sentence)

possivelmente

(indicating a lack of certainty)

possivelmente

(as a pro-sentence)

quem sabe

(indicating a lack of certainty)

quem sabe

(as a pro-sentence)

quiçá

(indicating a lack of certainty)

quiçá

(as a pro-sentence)

se calhar

(indicating a lack of certainty)

se calhar

(as a pro-sentence)

talvez

(indicating a lack of certainty)

talvez

(as a pro-sentence)

é possível

(as a pro-sentence)