do some baby-sitting 还是do some baby-sittings?

问题描述:

do some baby-sitting 还是do some baby-sittings?

第一个,不要S

do some baby-sitting
baby-sitting是不可复数名词,就像 push-up/ 俯卧撑
如果你说 do some baby sittings ,要+ s ,do some push ups 也是