| Subject | Russian | English |
| gen. | а вдруг | what if (Taras) |
| gen. | а вдруг | in case (I don't know, in case we ever bring girls here or something – Не знаю, а вдруг мы приведем когда-нибудь девочек сюда, например Taras) |
| inf. | а вдруг...? | suppose...? |
| idiom. | а вдруг | you never know (4uzhoj) |
| inf. | а вдруг | try me ("I don't expect you to understand my reasons".
"Try me". Побеdа) |
| gen. | а вдруг ... | could it be that (Abysslooker) |
| inf. | а вдруг...? | what if...? |
| gen. | а вдруг | maybe (But I thought maybe you could share it with Sam...; Emily, maybe this is that romantic encounter your horoscope foretold Taras) |
| Makarov. | а вдруг возникнет пожар? | suppose a fire broke out |
| gen. | а вдруг он не придёт? | suppose, what if he doesn't come? |
| gen. | а вдруг он не придёт? | suppose, he doesn't come? |
| inf. | а вдруг у него нет денег? | suppose he doesn't have any money? |
| proverb | как знать, а вдруг сегодня рухнет мир? | who knows but the world may end tonight? |
| idiom. | ну а вдруг | you never know (4uzhoj) |
| Makarov. | он называл меня на "вы" и мне это понравилось, а теперь вдруг на "ты" | he had spoken to me in the formal way in which grown-ups are addressed and I had liked it, but now he had suddenly changed to the familiar form |
| gen. | он скрывался несколько месяцев, а потом вдруг появился в Париже | after months in hiding he bobbed up in Paris |
