Were it not for friction, we ( ) walk on this earth of ours.
A: should not have been able to
B: would not be able to
C: were not able to
D: are not able to
A: should not have been able to
B: would not be able to
C: were not able to
D: are not able to
举一反三
- Were it not for friction (摩擦力), we ______walk on this earth of ours. ( ). A: were not able to B: should not have been able to C: would not be able to D: are not able to
- I wish I ________ to talk this over with him when he was here last night. A: had been able B: have been able C: were able D: should be able
- But for friction, people _________ neither walk, nor even stand up. A: can B: were able C: will be able D: could
- Without gravity, we ____ able to walk A: were B: should be C: can be D: should not be
- ________ the robots were able to have hands like ours, we would still need to design a way to control them.