He tried his best to work out the problem and ________he finish it with the teather's help.A.at the end B.in the end C.by the end

选B
in the end 最后
at the end 在结尾/末端
by the end of 到...末，没有by the end
本句的意思是：他尽最大的努力去解这道题，最后他在老师的帮助下完成了。
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B in the end 最后 的意思

B最后，最终
质量保证，求采纳

He tried his best to work out the problem and ___A_____he finish it with the teather's help.
A.at the end B.in the end C.by the end
at the end=finally 最后 固定词组
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B