今日四级单词：evaluate、flexible、guarantee
释义：vt. 评估，评价 同义词：assess, appraise 例句： - Teachers need to evaluate students’ progress regularly. - It’s difficult to evaluate the success of the project at this early stage.
释义：adj. 灵活的；柔韧的 同义词：adaptable, elastic 例句： - We need a flexible approach to solve this problem. - This material is very flexible and durable.
释义：vt./n. 保证；担保 同义词：assure, warrant 例句： - I can guarantee that the product is of high quality. - There is no guarantee of success in such a competitive market.