English modal verbs - Modal auxiliaries

Choose the correct modal auxiliary.

1. He (must/can) speak English but he hasn´t learned Spanish.

2. Jake (must/couldn´t) visit his Grandma this week. She needs help.

3. The pupils (needn´t/couldn´t) take their backpacks. It´s only a short trip.

4. (Must/Could) you carry my bag, please? It´s very heavy.

5. You want a computer. You (mustn´t/should) save your pocket money.