If come menstruation and is electronegative is the specification pregnant certainly?是什么意思？

If come menstruation and is electronegative is the specification pregnant certainly?

如果来月经而且试纸是阴性是不是说明一定没怀孕?

if

conj. 如果，倘若，即使，〈口〉是否，假设；n. 条件，设想；

例句
She was old enough to absent herself from the lunch table if she chose...
她长大了，可以自己做主不来吃午餐了。

come

vi. 来，开始，出现，发生；vt. 做，装扮…的样子，将满（…岁）；int. 嗨！；

例句
I've come looking for a bit of advice.
我特来讨教。

menstruation

n. 月经，行经，月经期间，赤龙，天癸；

例句
Whether does menstruate of the rice before menstruation adumbrate to come smoothly also classics?
月经前米有月经预兆是否也顺利来经?

and

conj. 和，与，而且，于是，然后，因此；

例句
I spend a lot on expensive jewelry and clothing...
我花很多钱购买昂贵的首饰和衣服。

is

vt.& vi. 是（be的三单形式；n. 存在；

例句
Bollinger 'RD' is a rare, highly prized wine.
博林格RD香槟是一种名贵的备受推崇的葡萄酒。

electronegative

adj. 负电的，带负电的；

例句
If come menstruation and is electronegative is the specification pregnant certainly?
如果来月经而且试纸是阴性是不是说明一定没怀孕?

the

art. 指已提到的人（物），指说话人与听者已知的人（物），用于独一无二的事物前，与形容词最高级和序数词连用；

例句
He did have a real knowledge of the country...
他对该国的确知之甚多。

specification

n. 规格，详述，说明书；

例句
Michelle will also spin a customer's wool fleece to specification at a cost of $2.25 an ounce.
米歇尔也会按顾客的要求为其纺羊毛呢，每盎司收费 2.25 美元。

pregnant

adj. 怀孕的，孕育着…的，富于想象的，富于成果的；

例句
Despite her wish to defy convention, she had become pregnant and married at 21.
尽管她不想遵循传统习俗，但她还是在21岁的时候就怀孕并且结婚了。

certainly

adv. 无疑，当然，确定，肯定；

例句
The Party was certainly not an official adjunct of the police department.
该党派肯定不是公安部门的官方附属机构。