---Itriedmanytimes,butIstillfailedtocompletetheexperime...

问题详情：

--- I tried many times, but I still failed to complete the experiment.  

--- Cheer up. _______ and the problem will be solved.

   A. If have a little effort                        B. Having a little effort 

   C. If you have a bit effort                       D. A bit more effort

【回答】

D

知识点：固定句型

题型：选择题