過去式：backtracked 過去分詞：backtracked 現在分詞：backtracking
...like along the way. Travel is only allowed in one direction, no backtracking allowed. If you do backtrack you will not have enough travel available to...
...cancer and the number of days related to eating out, Backtracking way to a random collection of patients with non-colorectal cancer patients...
...vehicle pollution, in particular, said the news shame the government, the has backtracked on a pledge to cut traffic on Britain's highways and ...