■ I think that he is a thief. 變被動語態不能是：That he is a thief was thought by me. 可考慮用：It is thought that he is a thief.（但這樣改意思與原來有較大差別了）　　

■在One can draw examples from genius in any field, from religion, philosophy, and literature to art and music, even in mathematics, science, and technical invention, although these are often thought to depend only on logic and experiment. 中，are thought 后接不定式屬于動詞 think 的一個常見用法，即我們通常說的“be thought + 不定式”句式（其中的不定式可以是一般式，也可以完成式或進行式）。如：　　

He is thought to be the best player. 他被認為是最佳運動員。

He was thought to be a spy. 他被認為是一名間諜。

He is thought to be hiding in the woods. 人們認為他躲在林子里。

He is thought to have been killed in an air crash. 人們認為他在一次空難中喪生了。

He is thought to have information which will be useful to the police. 人們認為他掌握了對警察有用的情況。