—Can we run across the road now?—No, we _     . We have to wait until the light turns green.

If you ___ stick to the unrealistic approach, the worse result will be waiting for you not far ahead.

It is hard to say what kind of person he is．Sometimes he is very friendly; at other times he ___ be very cold．

---Could I use your bike? ---Yes, of course you_________.

Delta, the American airline, is sometimes jokingly explained “Don’t expect your luggage to arrive” because it ______ be very slow.