am\are\is was\were been 分别是什么时态?
am\are\is was\were been 分别是什么时态?
be.am.is.are.were.was.been.being.分别是什么时候用的
am,is,are,be,been,was,were的区别
is----------was.are---------were.am---------?
am is are was were
are is were was am 分别是什么主语的be动词
is are were am was 分别是什么主语的be动词
何时使用BE【am/is/are/was/were/has(have)been】?
英文*是*怎么说的啊!到底是was.were,been 还是am,are,is啊?
is,am,are,was,were,being,been,to be怎么用
用“am/is/are/was/were"填空
用am is was are were造句