Since the airport is closed this morning, it must ______ last night.
A: snow
B: have snowed
C: have been snowed
D: have being snowed
A: snow
B: have snowed
C: have been snowed
D: have being snowed
举一反三
- Since the ground is white, it ____ last night. A: had snowed B: must have snowed C: must be snowing D: must have been snowing
- The flight was delayed for several hours because it _____ heavily last night. A: would snow B: has snowed C: snowed D: has been snowing
- I don’t know if it or not tomorrow. A: will snow B: snows C: has snowed D: is snowing E: was snowing F: will have snowed
- 4. Last winter it ________ on that mountain. A: snow B: to snow C: snowed
- The Triathlon（铁人三项赛） will be put off if it ___. A: will snow B: snows C: snowed D: is snowed