是be up to sb to do还是doing?

是be up to sb to do还是doing? be kind to do sth还是be kind to sb? be up to sb’s 是attract sb to do还是attract sb to doing? 是find sb. do还是find sb. to do call up sb doing sth还是to do sth? be up to do 还是 be up doing 哪个对 there will be sb+do还是to do? 是be difficult to sb 还是be difficult for sb? 是be free to sb 还是be free for sb thought ...如何判断是插入语还是sb.be thought to do =It is said to do...=sb be said to do It's up to sb to do it is up to sb to do 英语sb be to do be good for sb to do还是be good for sb do 是suggest sb to do 还是 suggest sb doing? 是offer sb sth还是 offer sb to do sth? 是advise sb.to not do还是advise sb.against