Phil So, transitive verbs in English take objects. The direct object is what receives or has the action done to it, and an indirect object is often who or what it is done for. So, if I say, "My father bought me a car", the car is the direct object, and I am the indirect object.
Phil Yes, so we can use 'that' clauses as the direct object of a verb. We often use these clauses with verbs of perception, like 'see', 'smell', 'hear', or verbs of thought, like 'think', 'know', 'believe'.
Phil Defining relative clauses use a relative pronoun like 'what', 'that', 'which', 'why' and 'how', to identify something. They can be both direct and indirect objects.
Examples Could you give me the tool that you were using? (你能给我你刚才在用的那个工具吗?)
Do you know the place where we're meeting? (你知道我们见面的地方在哪里吗?)
We gave an award to the person who made the most progress. (我们给进步最大的人发了一个奖。)
Phil In the examples above, the objects include the things being defined and the relative clauses, but sometimes we only need the relative clause itself.