Copernicus’s theory is now the basis ______ all our ideas of the universe are built.

What’s the weather like today —The radio says it’s .

The Internet gives people the chance to have the information they need ______ to them quickly and cheaply.

No one can ________ him in singing. He is the most popular singer among college students.[ ]

Let’s go for a picnic when it ______ this weekend.— But nobody knows when it _____ . I hate the rainy days.