英语核心语法解析-673：think动词的多重用法及否定句式转换现象
◎ think一词具备双重词性功能，既可以充当及物动词，也可以作为不及物动词使用。
① 当作为及物动词时，其核心语义指向“思考”或“观念形成”：
I think （that）she should go there. 我推测她应该前往那里。
② 作为及物动词的另一重要功能是表达“认知判断”，其句式结构呈现多样化：
think sb./sth. to be+宾语补足结构 （to be可选择性省略）
be thought to be+主语补足形式
think+that从句结构
think+it+宾语补足结构+不定式或that从句
We thought him （to be）an honest man. 我们判定他是个诚信之人。
（被动表达形式为：He was thought to be honest. to be不可省略）
I think her （to be）clever. 我判断她颇具才智。（被动表达为：She is thought to be clever. to be不可省略）
I think it is our duty to help her. 我认定协助她乃我辈责任。
I think it a good idea to go there. 我视前往当地为明智之选。
I think it best that you should come. 我主张你前来最为妥当。
This book is thought to be the best English grammar book. 该书籍被公认为顶尖英语语法著作。
③ 作为及物动词的第三个语义场是“意图规划”，其句式构造如下：
think to do sth. （适用于肯定与否定句式）
think+that从句结构
think+what从句结构
We thought to go on a holiday. 我们曾打算休假放松。
I didn’t think to meet you here. 我未料在此与你相遇。
I can’t think what you mean. 我难以领会你的意图。
④ 当作为不及物动词时，主要表达“思维活动”：
First think，then speak. 思虑先行而后言。
You have to think very quickly. 你需迅速进行思维运算。
⑤ 在表达“审视考量”语义时，think about与think of可互换使用：
She thinks too much about/of herself. 她过度关注自身。
I don’t care what other people think about/of me. 他人观点于我无关紧要。
I’m thinking about/of buying a bike. 我正评估购置自行车的可行性。
We have many things to think about/of. 我们面临诸多待审事项。
What do you think about/of the book？你对该书籍有何评价？
⑥ 当think about体现“追忆往昔”或“评估计划可行性”时，不可用think of替代：
Don’t think about the past any more. 停止追忆过往。
I’ve thought about it for some time. 我已对该议题深思熟虑。
⑦ 当think of呈现“关切挂念”、“灵光乍现”、“欲望规划”或“记忆唤起”等语义时，不可用think about替换：
He is always thinking of others. 他持续关怀他人。
I can not think of a suitable reply. 我难以构思恰当回应。
He longed for her return and thought of writing to her. 他渴望她归来，萌生致信之念。
Could you think of Tom，our old friend？你尚记得我等挚友汤姆乎？
⑧ think of…as结构表达“归类认知”：
I think of it as the most important problem. 我视其为核心难题。
It was thought of as possible. 众人认定其具备可行性。
⑨ think sth. over结构意为“深度审慎”：
You’d better think it over. 你宜慎重权衡此事。
We have to think the matter over. 我们必须周全考虑该议题。