No one knows for certain how the first Americans arrived in _____ is now the United States.

Thank you for all your hard work last week. I don’t think we ______ it without you.

I find it astonishing that John ______ be so rude tome.— Not astonishing at all. He is always rude to others.

Many people are_______. Let’s look after the_______ people.

I have a very clever dog. ________ name is Bobo. A．It’s