1. Semi-colons
Are these correct?

2. Mum said that I wasn’t allowed to go the party; I didn’t want to go anyway.

3. When I got home I noticed that the door was open and I remember locking it before I left; I’d been running late for work because my hairdryer broke so I had to do my hair in a braid that didn’t really work anyway.

4. Ancient Egyptians relied on the Nile to live; this civilisation would have never developed without the river.

5. My ‘dream car’ is a red Mazda RX8; because I love how sporty it looks.

6. As he wrote the instructions on the board, Mr Potter became very annoyed; the students were very unsettled and were all making a ruckus.

7. Before she opened the envelope; she checked the return address.

8. The windows were filthy and badly needed cleaning; the toddlers had wiped their sticky hands all over them.