He's Jack's uncle.解析:He's = He isJack's 这个不是 Jack is的缩写,而是物主代词,表示“Jack的”整句意思是:他是(He's)杰克的(Jack's)叔叔.

The man (with glass) is Sam's uncle.对括号部分提问 (Which ) (man )is Sam's uncle?John plays computer games at home.改为否定句 John (doesn't)(play)computer games

is 后面没有动词了,has 后面有动词的过去分词.

翻译过来是“杰克是艾玛的叔叔吗?”回答如果是肯定回答就是Jack is Emma's uncle.或者Yes,he is.如果是否定回答是Jack is not Emma's uncle.或者No he is not.

是 he is 不可能是was

他是杰克的叔叔

he's 有两种情况:he has 他有(缩略语);例句:A journalist all his life, he's now brought out a book. 他当了一辈子新闻记者,如今已出了一本书.he is 他是(缩略语);例句:I am afraid he's ill.恐怕他生病了.

撇好s是所有格,表示某某的东西,这里没有上下文没法确定是什么东西.

be 动词is的缩写

意思当然不一样