I spend my free time [most] watching TVI spend my free time [most] watching TV

I spend my free time [most] watching TVI spend my free time [most] watching TV
I spend my free time [most] watching TV
I spend my free time [most] watching TV

I spend my free time [most] watching TVI spend my free time [most] watching TV
I spend my free time [most] （ in ) watching TV.
正确翻译：我的业余时间大多是看电视度过的.
解析：这个空填介词in,即sb.spend some time ( in ) doing sth 某人花.时间做某事,这个介词in可以省略；另外sb.spend some time on sth 某人在事/物上花.时间.记住,后面如果有doing sth 就用介词in,可以省略,如果后面是名词,就用介词on
有不明白的请继续追问,

我打发业余时间[最]看电视