Bonjour pouvez vous m'aider svp

2. Mettez les verbes entre parenthèses à la forme qui convient (prétérit simple ou prétérit en be + V-ing).
EXEMPLE -->
The ogre (have) breakfast when the little boy arrive).
The ogre was having breakfast when the little boy arrived.

a. As he (walk) towards the enchanted forest, he (hear) a call for help.

b. The wicked witch (prepare) her potion when her glasses (fall) in the cauldron.

c. The princess (brush) her long hair and (sing) when Prince Charming (hear) her beautiful voice.​