Beginner Level 初级 (chūjí)
The answer to the test is A.
Reread the sentence:
Tīnɡshuō Běijīng kǎoyā hěn hǎochī, yúshì, wǒ hé péngyou juédìnɡ qù chángyicháng.
听说 北京 烤鸭 很 好吃，于是，我 和 朋友 决定 去 尝一尝。
It is said that Beijing roast duck is very delicious, so we decided to give it a try.
“于是 (Yúshì) So/hence” is a conjunction used between two consecutive events. Usually it is placed before the latter event, indicating that it follows the first event. The writer decided to try the Beijing roast duck after he heard that it was delicious.
“但是 (Dànshì)” is a conjunction similar to “but” in English.
“可是 (Kěshì)” also means but, though it is less strong and less formal than “但是 (Dànshì).”
Māma bú zài jiā, wǒ yòu bú huì zuòfàn, yúshì wǒ jiù qù wàimiàn chīfàn le.
妈妈 不 在家，我 又 不 会 做饭，于是 我 就 去 外面 吃饭 了。
Mom was not at home, and I can’t cook, so I ate out.
Suīrán shēnghuó hěn kùnnan, dànshì tā háishi jiānchí ràng háizi shàngxué.
虽然 生活 很 困难， 但是 她 还是 坚持 让 孩子 上学。
Although it is quite difficult, she still insists on sending her child to school.
Tāmen shì jiěmèi, kěshì guānxi bú tài hǎo.
她们 是 姐妹，可是 关系 不 太 好。
They are sisters, but they don’t get along well with each other.