1)can could 表示能力;可能(过去时用could), 只用于现在式和过去式(could)。be able to可以用于各种时态。They will be able to tell you the news soon.他很快就能告诉你消息了。 2)只用be able to a. 位于助动词后。 b. 情态动词后。 c. 表示过去某时刻动作时。 d...
We tend to look on nature conservation as some kind of favour that human beings are granting to the natural world. The error here is far too deep: not only do humans need nature for themselves, but the very idea that humanity and the natural world ...
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