1.I told her that either I would have to buy a new mower or let the grass grow.either ..or 连接的2个成分 必须一致吧.那么or 后面应该是or I

1.I told her that either I would have to buy a new mower or let the grass grow.either ..or 连接的2个成分 必须一致吧.那么or 后面应该是or I would have to let the grass grow .请问 or 省略的I would have to 怎么回事?
2.the sheer volume of rubbish we produce worldwide threatens to overwhelm us 这里的worldwide 是否是 副词 ,还是形容词,如果是副词的话那就是地点副词了 ,因为没看到 介词啊 .（好像没听说过worldwide还是地点副词!)
3.有没有sb remain to do sth 某人留下来做某事的句型..
suspect sb to do sth 怀疑某人做某事句型
suspect sb +adj 句型