如果是过去式,they (can) play quite well

如果是过去式,they (can) play quite well how many cakes can i have,momnone,dear.they _______ for your father.A prepare B preparedC have prepared D were prepared如果是d为什么用过去式 can过去式 be taken aback.是什么时态?They met once a month.是什么时态?如果是过去式,怎么没有标志词? PL是啥意思呢? They're coming this morningbe coming 可以是过去式》? they的过去式是什么? They want to learn Chinese history and culture 的过去式是want变过去式还是learn变过去式 It is the only way they can read sometimes.如果是,是什么从句? The thieves dropped the torch and ran away as quickly as they could.这句话中as quickly as they coucould是can的过去式.can是情态动词 应该没有过去式啊?为什么会有?还有就是 不是应该是 as sb as sth 本人实在学力不 Canners can can what they can, but can not can what they can not can.是什么意思快,急是绕口令 关于pl与常pl比方说pants,解释里是pl,意思是pants为复数而像chance,这个词,有一个意项什么概率,前面是（常pl）这里意思是chance作这个意思时是复数还是作这个意思时要加s成为复数?如果是要加s can是情态动词吗?can的过去式could也是情态动词吗?还有一个问题 、The boys _ carefully,but they could_nothing.( )A look-see B watch-saw C looked-see D looked- saw can的过去式是could吗?may的过去式是might吗?shall的过去式是should吗?will的过去式是would吗? need情态动词的过去式是什么?need情态动词的过去式是什么如can是could could 是can的过去式,那为什么could you help me 用could,又不是过去式 谁英语好解释一下”could是can的过去式, Could开头的疑问句是can的过去式吗?