A feather falls slower than a stone only because the air holds the feather back more than it ______ the stone.

. He was late for the meeting because the bus he took ______ halfway. 

Through the satellites, we can send and _______ messages.

The Internet is ___ more and more important ___ in our everyday life.

---What bad weather! It’s raining all these days. ---Yes, the river has _____ two feet.