The noun 议员 (yìyuán) means "legislator," "council member," or "member of parliament." It refers to an elected official who serves in a legislative body. It can be combined with a party name, such as 保守党议员 meaning "Conservative Party member of parliament."
那位议员提出了一项新的教育法案。
nà wèi yìyuán tíchū le yī xiàng xīn de jiàoyù fǎ'àn.
That legislator proposed a new education bill.
几位议员对这个政策表示反对。
jǐ wèi yìyuán duì zhège zhèngcè biǎoshì fǎnduì.
Several legislators expressed opposition to this policy.
他当了十年的议员,做了很多实事。
tā dāng le shí nián de yìyuán, zuò le hěn duō shíshì.
He served as a legislator for ten years and accomplished many practical things.