| 5000 Vocabulary List for Visiting Scholars in the USA - Page 372 | |||
| Word | Type | Used in a Sentence | Synonym |
| objection | noun | What is your objection to me going? | opposition |
| objective | noun | The trip objective is to have fun. | goal |
| adj. | We need an objective appraisal. | unprejudiced | |
| obligation | noun | We have an obligation to help her. | duty |
| oblige | verb | We will oblige her by not leaving. | favor |
| verb | They were obliged to him for his help. | indebted | |
| obscure | adj. | He was an obscure government official. | little-known |
| observation | noun | We knew this by observation. | examination |
| noun | He made an observation to me about her. | remark | |
| observe | verb | We shall observe exactly what happens. | watch |
| verb | You will have to observe the rules. | follow | |
| verb | Yesterday I observed my birthday. | celebrated | |
| observer | noun | The observer found no problems. | viewer |
| obstacle | noun | We will place no obstacle in your path. | barrier |