the old man used to take a walk along the river after supper大概的意思我知道是晚饭后老人沿河边散步

句子的动词的时态是错误的.
used to表示过去常常的意思,所以take应该用一般过去式表示,即应该用took代替take.
句子应该是The old man used to took a walk along the river after supper.可以麻烦你帮我翻译一下吗这个老人过去常常在晚饭后沿着河边散步