Definition: to not be certain Level: B2
这个计划的成功不确定。
The success of the plan ___is ___in ___doubt.
如果你对答案不确定，就寻求帮助。
If you ___are ___in ___doubt about the answer, ask for help.
他对公司的忠诚度曾经不确定。
His loyalty to the company ___was ___in ___doubt.
