1. I am going to meet mum ............. travelling to Paris.

when

while

before

at

2. ............. the light went off, they screamed.

just as

when

before

at

3. ............ the bill rang, the children ran out of the school.

before

after

as soon as

till

4. Do not leave ............ you ask for permission.

when

while

until

as

5. ............. the boy was playing, the car was coming towards him.

when

while

as soon as

till

6. You can receive the contract ............. you sign.

when

while

as soon as

as