could
[modal verb]
1 — used as the past tense of can
2 a — used to say that something is possible ▪ You could [=might, may] be making the biggest mistake of your life! ▪ This could be our only chance to get our of here. ▪ His recovery could take months. ▪ This medicine could help your cold. ▪ The evidence is not conclusive, but he could (very well) be right. ▪ This news could mean trouble. ▪ Did you think he could still be alive? ▪ That kind of thing could happen to anyone. ▪ They could still succeed, although it's not likely. ▪ I think he could be trying to cheat us. ▪ Do you think he could [=can] really be serious? ▪ Could this be our ride? [=is this our ride?]
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