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文章标题
Gum Disease Could Be Linked to Higher Risk of Dementia, Especially in Severe Cases
牙龈疾病可能与较高的痴呆风险有关，尤其是在严重的情况下
1. gum
KK /ɡʌm/
n. 齿龈
拓展
chewing gum 口香糖
释义
either of the firm areas of flesh in the mouth to which the teeth are attached
2. dementia
KK /dɪ'mɛnʃə/
n. 痴呆，精神错乱
释义
a serious mental disorder caused by brain desease or injury, that affects the ability to think, remember and behave normally
3. be linked to
跟...有关
4. severe
KK /sɪ'vɪr/
adj. 严重的
搭配
in severe cases 在严重的情况下
in less severe cases 在不太严重的情况下
Para. 1
①Researchers from several universities studied 4,559 participants, who did not have signs of dementia at the start of the study, over an average of about 18 years to assess their gum health and whether they developed dementia or cognitive decline later in life.
①来自几所大学的研究人员对4559名在研究初始并没有痴呆症迹象的参与者进行了平均约18年的研究以评估他们的牙龈健康状况，以及他们是否在以后的生活中患上了痴呆症或认知能力下降。
1. sign
KK /saɪn/
n. 征兆，迹象
2. over+时间
KK /'ovɚ/
prep. 在一段时间里
例句
She has not changed much over the years.
这些年她没有多大变化。
3. an average of
平均
4. assess
KK /ə'sɛs/
v. 评估
释义
to make a judgement about the nature or quality of sb/sth
5. cognitive
KK /'kɑɡnətɪv/
adj. 认知的，感知的
释义
connected with mental processes of understanding
搭配
cognitive psychology 认知心理学
6. decline
KK /dɪ'klaɪn/
n. 衰退，下降
7. develop
KK /dɪ'vɛləp/
v. 患病，出现问题
释义
to begin to have sth such as a disease or a problem, to start to affect sb/sth
例句
Her son developed asthma when he was two.
她的儿子两岁时患了哮喘。
长难句解析
Researchers (主语) from several universities (后置定语) studied (谓语)4,559 participants (宾语), who did not have signs of dementia at the start of the study (非限制性定语从句), over an average of about 18 years (时间状语) [to assess their gum health and (whether they developed dementia or cognitive decline later in life) (宾语从句)](目的状语).
该句是主从复合句，主句是“主谓宾”结构，主干为 Researchers studied 4559 participants，后面为 who 引导的非限制性定语从句，对 participants 进行修饰，说明这些参与者的身体状况，over an average of about 18 years 为介宾短语作时间状语，说明研究的时间跨度，后面 to assess...later in life 为不定式结构作目的状语，表明研究目的，其中嵌套了 whether 引导的宾语从句，与 gum health 一起作为 assess 的并列宾语。
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