No one knows exactly when our ancestors started talking,but new evidence suggests _______might have happened a long time ago.
No matter how healthy you ________ be, you need to consult a doctor from time to time.
Many dog owners treat their pets like human beings, ________ if they do not have children of their own.
I really don't know how to thank you, but for your help, I ________ my lost necklace.
After ________ seemed an endless wait, it was her turn to enter the interview room.
I'm a bit green at ________ video editing, so it takes me ________ long time to edit these things.