he is in bed.是对的，he in bed .句子成分不全，缺少谓语/系动词，简单的句型主谓宾、主系表结构
He is in bed.这句是对的，原因是句子结构是 “主系表结构”请百度百科，关键字“主系表结构”
He is in bed.
He is in bed.这句是对的，原因是句子结构是 “主系表结构”he in bed .句子成分不全，缺少谓语/系动词，简单的句型包括主谓宾、主系表结构
