I think cats are easy(keep)____ 应填keep的什么形式?

I think cats are easy(keep)____ 应填keep的什么形式? I think （）空中填keep的相应形式 a pet is easy cats are easy（容易的）to keep.我认为easy是形容词又不是动词那么easy与keep之间为什么填t we can't keep him ____(out)填正确形式 cats are easy to look after.的同义句 ____　____ ____ ____ after c I think dogs are ----- ------- ------ cats ____(keep)him out!I don't like him.填什么 解释一下为什么 keep后面接动词的什么形式? I think it's important to keep the room clean.I think ____ _ Keep加动词什么形式 keep differing____him填什么介词 keep的动词ing形式