Hetalkedalotaboutthingsandpersons________theyrememberedintheschool.
B
things 和 persons 是先行词 .当定语从句要修饰的先行词是既表示人 , 又表示物的名词时 , 其关系代词要用 that
The other timing system belongs in our internal clocks，which，left ________，would tie the body to a 25-hour rhythm.
Countrylifeisbetterthancitylife________itoffersfreshairandnoiselessenvironment
The conclusion from the study is not definite; it is just ________.
Youngerchildrenarecurious________howthingswork，andmanyofthemwanttotakeaparteverythingwithintheirreach.