Unique rules when forming that grammar are highlighted like this
Example sentences follow these rules too!
Joining and Nesting Markers:
Verb[た/る] - means that dictionary form and ta form are accepted.
Verb[causative[て]] - means て form of the causative form of the verb.
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使用域一般
物
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Aものと思っていた is an expression used when the speaker/writer was convinced that A was the case, but actually (and often surprisingly) it is not. Clarifying comments often follow after が/けど, if the context is not easily understandable.
Used with expressions like てっきり、驚く and so on for emphasis.