1.There (be) no guests at all since I (leave).
=>There have been no guests at all since I left.
2. I (never forget) what you (just say).
=>I will never forget what you have just said.
3. Someone (steal) my handbag on the bus.
=> Someone has stolen my handbag on the bus.
4. Hurry up or you (be) late for class.
=>Hurry up or you will be late for class.
5. I (start) learning English when I (be) in grade 6.
=>I started learning English when I was at grade 6.
6. Would you mind (open) the window?
=>Would you mind opening the window.
7. Some animals (not eat) during the winter.
=>Some animals don't eat during the winter.