The situation is bad, but it could be worse. (now)
请问上面这句中的could的用法是
算2a 还是 3a ??
could 的用法:
1.can 过去式
He said he could do it.
2.表现在或未来的可能，意思同can的语气较can来的较委婉，较不确定
a. 现在有可能 (possible now)
The story could (有可能) be true, but I don't think it is. (不能用 can be true)
b. 未来有可能 (possible in the future)
I don't know what time Liz is coming. She could (有可能) get here at any time.)
3.表假说法中的与现在事实相反(could + V)或与过去事实相反(could have + Vpp)
a. 现在事实相反(could + V)
I'm so tired. I could sleep for a week. (now)
b. 与过去事实相反(could have + Vpp)
I was so tired. I could have slept for a week, (past)
The situation was bad, but it could have been worse. (past)