I think he is very old.这个句子有错吗?句中,thank 是动词,is也是,中间怎么不接to或者后者+ing?

Is he very happy Yes,I think ___填什么 I think he is very old.(该否定句） I ---- -----he-------very old. I think he is _______younger than before.A、very B.very much C.much D.many Do you think Mr White is a serious man?-In fact,I think he is very f_____ The boy is fat.I think he is a Iittle o----. The boy is o––– at the moment,I think he is ill again. (Personal)_,I think he is a very nice partner,though you may not agree为什么 The boy is very stubborn and I don't think he will a___your advice I think he is very handsome这句话有语病吗 I think math is very difficult.同义词 I think it is very interesting 是什么意思 but I think it is very this is little tonny,who i think has done very well though ,he is so young怎么知道I THINK 是插入语,为什么是WHO而不是WHOM? I think geography is very interesting 对 very interesting 提问 I think you English is very good. I think you English very good. which is right I think he is sure to___(succeed). i donot think he who is right I think he is must abolish.