The plane ________ when I arrived at the airport．
| A．have gone | B．went |
| C．is going | D．had gone |
Hurry up, _______ you will miss the early bus.
| A．otherwise | B．if | C．and | D．but |
---Shall we meet at 6:00 or 7:00?
---________.
| A．Any time is OK | B．At any time |
| C．Yes, at 6:00 | D．Well, either time will do |
Many people claim that they have seen UFO with their own eyes, _____ I personally doubt.
| A．that | B．which | C．when | D．where |
—You _____ a meal this evening. I had dinner at a restaurant with Tom.
—Well, why didn’t you phone me and let me know?
| A．should not cook | B．don’t need to cook |
| C．needn’t have cooked | D．should have cooked |
Water, which seems so simple and common, is _____ makes life possible.
| A．that | B．what | C．which | D．how |