advice是用 a 还是an 还有 E-mail advertisement E-cat

问题描述:

advice是用 a 还是an 还有 E-mail advertisement E-cat

advice 不可数,用a piece of或some
E-mail advertisement E-cat前用an

都用an

advice建议,为不可数名词,一条建议:a piece of advice
E-mail advertisement E-cat前用an
tips:元音因素开头的名词前用an,辅音因素开头的名词前用a