They all over the country, so they plan some other countries.
A. have traveled, visit
B. traveled, to visit
C. have traveled, to visit
D. traveled, visit
网友回答
A. have traveled, visit
B. traveled, to visit
(答案→)C. have traveled, to visit
D. traveled, visit
解析：句意：他们已经游遍了全国，因此他们打算去参观一些其他的国家。结合语境可知前文描述的是现在已经完成的动作，故用现在完成时态。下文plan后一般接动词不定式作宾语，表示具体的将要进行的动作，故选C。