区别:needn't have done表示过去没必要做而实际上做了;
didn't need to do表示过去没必要做而实际上也没做.
根据前面的句子They had plenty of bread来判断,she没必要买面包而实际上买了,所以选C.
区别:needn't have done表示过去没必要做而实际上做了;
didn't need to do表示过去没必要做而实际上也没做.
根据前面的句子They had plenty of bread来判断,she没必要买面包而实际上买了,所以选C.