部分原因是

部分 buˋ fenˋ

(Part, Parts, Portion, Portions, Section, Sections) Portion, Portions, Part, Parts, Section, Sections

部分原因 buˋ fenˋ yuanˊ yinˉ

(Part of the) Part of the reason

原因 yuanˊ yinˉ

(Cause, Causes, Factor, Factors, Reason, Reasons) Cause , Reason , Factor , Cause, Causes, A cause, The cause, The causes, Reason, Reasons, A reason, The reason, The reasons, Factor, Factors, A factor, The factor, The factors

是 shiˋ

Is, To be, Am/Are/Is/Was/Were, Being, Yes