(2009·江苏高考)He did not regret saying what he did but felt that he________it differently.

Itriedtoworkon,butIgotsotiredthatIcouldnolonger________.

The word “track” ________ a path which is made of earth ________ having a surface covered with other materials.

______ is known to us all, the old scientist, for ______ life was hard in the past, still works hard in his eighties.

He will arrive in Shanghai _____ three hours. Let’s go to meet him.