他们解出那些数学题有困难 They＿ ＿ ＿ ＿the difficult math problem.
问题描述：
他们解出那些数学题有困难 They＿ ＿ ＿ ＿the difficult math problem.
答
have trouble working out
他们解出那些数学题有困难 They＿ ＿ ＿ ＿the difficult math problem.
have trouble working out