
am/is的过去时是were和was.1、abbr. 调频du,调谐,调幅(zhi amplitude modaolation)2、vi. (用于第一zhuan人称单数现在时)3、aux. (与v-ing连用shu构成现在进行时,与v-ed连用构成被动语态)4、n. (柬)安(人名)
例句
Most of the problems were due to human error.
多数问题都是人为错误造成的。
She was not only intelligent but also very musical.
她不仅聪明,而且极具音乐天分。