单数。
anything是不定代词，作主语时谓语动词要用单数。
1、常用不定代词有：some（something,somebody,someone,somewhere）,any（anything,anybody,anyone,anywhere）, no（nothing,nobody,no one）, every（everything,everybody,everyone,everywhere）,all,each,both,much,many,（a）little,（a）few,other（s）,another,none,one,either, neither等.
2、如果主语是some（something,somebody,someone,somewhere）,any（anything,anybody,anyone,anywhere）, no（nothing,nobody,no one）, every（everything,everybody,everyone,everywhere）,each,a (little), another,none,one,either 等时,谓语动词用单数形式.
3、如果主语是all,both, all, others 等时谓语动词用复数
anything else可数吗
enything else 应该不可数