常用that的情况如下:
a、非正式用语中可用来代替 whowhomwhich,但不能代替whose .
b、先行词前有最高级修饰时.
c、先行词前有the first,the last,the next修饰时.d、先行词前有the only ,the very,the just修饰 时.e、先行词前有all,any,every,no,much,little,few,none修饰时.
f、先行词是everything,everybody,nothing,nobody,something 时.
g、先行词前已有疑问代词whowhomwhich时,常用that,以免重复.
h、关系代词在从句中作补语或做there be真主语时,常用that,并常省
i、口语中代whenwhywhere可省,但代where时,先行词必是the place
j、当人、物共作先行词时,常用that .